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UK March - April 2010




mother Plants Picking The Best

Get the Skinny on

Fads and falLacies which co2 are you? Win BIG! Grow BIG! ENTER ONLINE

Coming up on the Web Speed Read 1. When plants are provided with the proper CO2 concentration, they can achieve optimal photosynthesis resulting in record growth. Choose the best enrichment method for your situation. 2. T  he next generation of LEDs is here and they’re invading grow rooms across the globe. What makes them so powerful and efficient? Find out on 3. T  he composition of a nutrient solution determines the health and growth rate of plants in hydroponics. But it comes down to more than just macros and micros. In fact, more than 60 elements are required for plant growth.

Win Big! Grow Big! with Maximum Yield When it comes to growing HUGE yields, Maximum Yield has you covered. The Maximum Yield Win Big…Grow Big competition is now open to UK residents with exclusive prizes from the biggest names in the industry including Nutriculture, Canna and PowerPlant. Multiple entries are accepted. No purchase is necessary. If you want to GROW BIG in 2010, this is the competition for you. Enter by April 15 at



VOLUME 9 – NUMBER 6 March/April 2010 Maximum Yield is published bi-monthly by Maximum Yield Publications Inc. 2339A Delinea Place, Nanaimo, BC V9T 5L9 Phone: 250.729.2677; Fax 250.729.2687 No part of this magazine may be reproduced without permission from the publisher. If undeliverable please return to the address above. The views expressed by columnists are a personal opinion and do not necessarily reflect those of Maximum Yield or the Editor. Publication Agreement Number 40739092 PRESIDENT/PUBLISHER - Jim Jesson GENERAL MANAGER - Don Moores BUSINESS MANAGER - Linda Jesson SALES DIRECTOR - Lisa Lambersek EDITOR - Jessica Raymond ADVERTISING SALES 250.729.2677 Linda Jesson - Lisa Lambersek - Julie Madden - Ilona Hawser - Gaby Morin - PRODUCTION & DESIGN Pentti Tikkanen - Alice Joe - Wes Cargill - ACCOUNTING - Lee Anne Veres

Visit today and check back often for updated exhibitor listings, venue information and registration forms for the 2010 Indoor Gardening Expo tour.

Behind the Lens – International Exposure Could Be Yours Attention Photographers: Have your pictures seen internationally by thousands of readers of Maximum Yield magazine. If your photo is chosen, it will be published on the cover of one of the following: Maximum Yield USA, Canada, French Canada, Australia, and of course, UK. The Behind the Lens competition closes June 1, 2010. Flip to page 50 for more details.

Tell us what you think at We’d love to hear from you.

contributors Dr. Lynette Morgan holds a B. Hort. Tech.

degree and a PhD in hydroponic greenhouse production from Massey University, New Zealand. Lynette is a partner with SUNTEC International Hydroponic Consultants and has authored five hydroponic technical books. Visit and for more information.

Erik Biksa holds a diploma in agriculture

with majors in fertilizer sciences and crop production. Erik has amassed over 18 years of indoor gardening experience and intensive research. Since first appearing in Maximum Yield in 1999, the “Ask Erik” column and numerous articles have reached growers throughout the world.


MAXIMUM YIELD UK - March / April 2010

Brian Johns is driven by his passion to change the way people think about agriculture. He encourages natural food production in soil and hydroponic farming. Brian owns and operates Happy Family Farms in Flint, Michigan where he resides with his wife and business partner, Becky, and their three children, Sara, Stephen and Noah.

Matt LeBannister developed a green thumb

as a child, having been born into a family of experienced gardeners. During his career, he has managed a hydroponic retail store and represented leading companies at the Indoor Gardening Expos. Matt has been writing articles for Maximum Yield since 2007. His articles are published around the world.

UK DISTRIBUTION Growth Technology Hydrogarden Future Harvest Developments Europe Nutriculture UK CANADIAN DISTRIBUTION Brite-Lite Group Biofloral Eddis Wholesale Greenstar Plant Products Inc. Hydrotek MegaWatt Northern Hydroponic Wholesale Quality Wholesale USA DISTRIBUTION Aurora Innovations BWGS + BWGS West + BWGS East General Hydroponics Hydrofarm Hydro International National Garden Wholesale / Sunlight Supply R & M Supply Tradewinds AUSTRALIAN DISTRIBUTION Dome Garden Supply Futchatec Growth Technology Holland Forge Hydraspher

CONTENTS march / april 2010 FEATURES 20


Your How-to Guide to Growing Irish Shamrocks


Weird Plant Happenings


Container Herbs for Beginners


Fads and Fallacies


Wind, Earth, Water or Fire: Which CO2 Are You?


Micropropagation - The Culture of Tissue


Selecting and Maintaining Mother Plants

by Dr. Lynette Morgan

by Emma Cooper

by William Texier

by Erik Biksa

by Brian Johns

by Matt LeBannister

28 34

DEPARTMENTS 4 6 From the Editor 6 Letters to the Editor 8 Ask Erik 10 MAX Facts 14 Product Spotlight 43 Do You Know? 44 You Tell Us


49 Check Your Growing IQ 50 Coming up in May - June MAXIMUM YIELD UK - March / April 2010


FROM THE editor

jessica raymond

Spring is here and if you haven’t already got something growing – now is the perfect time to get started. This issue is packed with tips and tricks to bring you the best grow ever! From the simplest of herb gardens to more complex gardens, our writers this issue have you covered. Be sure to follow up with our online extras at and while you are there, don’t forget to enter our “Win Big, Grow Big” UK contest where you have four chances to win grow gear for your garden. Once your garden is in full bloom, be sure to send us pictures. Our first ever “Behind the Lens” cover contest gives you, the grower, the creative license to shoot the photo to be published on an upcoming cover of Maximum Yield. Contest closes June 1, 2010 so get snapping.

Jessica Raymond, Editor

letters to the editor Trading Up I would like to tell you about a company called Trade Hydro in Yorkshire. I am new to indoor growing and only started in the summer as my greenhouse blew away and destroyed my orchids. As I was left wondering what to do next, I saw last year’s Jan/Feb issue of UK featuring an article on orchids. I though I would give it a go, and as I had never done this before, I was a bit dubious to say the least. After a long time on the Internet I found Trade Hydro. The service I received was second to none. I managed to get a plug and grow kit with a free bulb for just £50. Trade Hydro in West Yorkshire was just ace and everyone in the UK who grows indoors needs to know about them. Keep up the good work with your magazine. Kind regards Scott Vaughan

Click and Share It I noticed with the past several issues of Maximum Yield a funky new look to your covers and the graphics used inside the magazine. I have some great shots from my indoor gardens that would work well on the cover or in your magazine and would be interested in submitting them for publication. Fred Dunn

We encourage you to submit your high quality photographs for our first ever, readersubmitted cover contest – Behind the Lens. This contest is open to everyone until June 1, 2010. Five winning photos will be chosen and published on the covers of Maximum Yield USA, Canada, French Canada, UK and Australia. Please see our ad on page 32 for more information or visit for full contest rules regulations.


MAXIMUM YIELD UK - March / April 2010

Review and Praise

"Everything in

your publication is My name is JC Gray and I recently very educational picked up an issue of MY at a local and informative." shop. At first glance I assumed it was a catalogue or just a magazine filled with products for sale. I soon discovered that everything in your publication is very educational and informative. I find Bob Taylor’s articles very helpful. The tips he provides are an excellent blueprint for anybody working with any system to start from. I just wanted to say thanks for providing a resource filled with good nuggets! Thank you for your time, and again, excellent mag. Hope all is well at the MY headquarters. Much respect JC Gray

Lighting the Future I just wanted to get some feedback on LED grow lights. Please e-mail me back any links or information. I want to know if whatbelievers’ claim is true.




Josh Adams

You’ve come to the right place for answers. As LEDs are constantly evolving, we asked our resident expert Erik Biksa to detail this hyped up technology in his latest article on, “Next Generation LEDs: The Diodes Strike Back.” His three-part series will examine first-generation LEDs and upgrades in technology available in this lighting option today. You may also wish to stop by and join in on the LED Debate with hundreds of other MY fans. Maximum Yield reserves the right to edit for brevity.

We Want To Hear From You! Write Us At: Maximum Yield Publications Inc. 2339A Delinea Place, Nanaimo, BC Canada V9T 5L9 or



Do you have a question for Erik? Forward it to with the words “Ask Erik” in the subject line, and your answer will be printed in an upcoming edition.

Hey Erik, I grow hydroponically. The system I like to use is a DWC (deep water culture). Each plant is grown in a 23 litre bucket, with a 13 centimetre mesh pot on the top that is held up by the lid. I keep a couple of air stones in each bucket and have those all connected to a high-output air pump that is made for hydroponics. The buckets are bubbled 24/7. There is a lot of aeration due to the size of the air-pump I am using. Everything had been going great. To try and get better crop quality I switched over to organics. I am using a 100 per cent organic crop feeding program, and have followed the manufacturer’s directions. After I transplant, the plants look great for a few days, then things appear to go downhill. The leaves start to turn yellow, and the roots don’t develop as well as they did before. They are starting to get a slime growing on them and inside the bucket. I monitor the pH and have found that it just keeps going up, and up. I am worried that all the pH down I have been adding might be creating a nutrient lock-out or causing some of the problems I have been seeing? Help! What can I do? I have never experienced these types of problems before, when I was using synthetic nutrients in my DWC system. The temperature is pretty good, but I have noticed that the buckets tend to heat up. Could this be causing my problems? Thanks, Stressed


MAXIMUM YIELD UK - March / April 2010

Stressed, Let’s hope we can have your pen name changed to “stoked” next time you write back by solving these issues that you are describing. Temperature is always a big factor, and is especially critical in hydroponics. Before when you were using a “sterile” nutrient solution from chemically derived nutrients, you may have been on the threshold of problems, but were lucky enough to avoid them. The high level of aeration coupled with the sterile nature of synthetic nutrients might have been just enough to keep pathogens away and nutrient availability to your plants intact. With organics, while a portion of the nutrients are available directly to the plant, there will be a portion that is being supplied as “raw,” requiring microbes, etc. to convert the cruder forms of nutrients into forms that the plant can easily take up. In a soil or soilless growing medium, the microbes required to accomplish this have plenty of “space” to live. Since there is very little growing medium in your system, the microbes required for these important conversions can only try and live in the solution, on the inner sides of the bucket and directly on the roots. This means that some of the species that are important in converting organic matter to plant food might not have a place to live. Remember that these organisms, for the most part, evolved in growth mediums (soil), not water; so that’s the type of environment they prefer.

You are supplying the microbes with plenty of oxygen from your high-powered air pump. This is causing a population explosion in the species that are able to thrive in the watery environment, while the solution, growth medium, roots, etc. may be lacking other species because it is not a conducive environment for them to multiply in and perform the necessary functions. Basically, you may have wound up with a microbial imbalance which in organics can equate to a nutrient imbalance. The warmer temperatures and raw, undigested materials can create a situation where pathogens may develop, and in severe cases cause root rot. The constantly rising pH may be indicative of a microbial population explosion from the abundant food sources combined with high levels or aeration. Unfortunately, it appears that this has become an unbalanced population in terms of the species diversity. The additions of substantial quantities of chemical or organic pH down products can in fact create nutrient imbalances. If using chemical pH control products at significant levels, the microbial populations may suffer, furthering imbalances in the species diversity. Aside from recommending a nutrient system better suited for your DWC methods, I can advise the following: • reduce the level of aeration • include a broad spectrum of digestive enzymes in your feeding program • occasionally re-introduce balanced microbial populations by adding well formulated beneficial inoculants at half strength • reduce the level of carbohydrates and other potential food sources for microbes that you have been adding • ensure that the nutrient you are using is not too “thick” and does not contain excessive levels of undigested organic materials • be sure to completely empty the buckets out once per week and start with fresh solution; you may find that doing this even more frequently will have a positive effect. Hopefully, this will get things back on track, and I admire that you have been willing to experiment in an attempt to improve the quality of your harvests. Highest Regards, Erik Biksa


MAXIMUM YIELD UK - March / April 2010




hydroponic news, tips and trivia from around the world

Feed 5000 This past winter, thousands met at Trafalgar Square in London for a feast with 5,000 place settings. Tonnes of generously donated fresh produce from farms, packers and markets were received that were ‘outgraded’ for being cosmetically imperfect and which would have been wasted though they were still good to eat. An army of volunteers, including FareShare, the largest food redistribution charity in the UK, assisted with the delivery, handling, preparation and serving of the food. Smoothies from fresh surplus fruit was made by a team of bicycle-powered smoothie makers and handed out to passersby. Leading chefs performed live cooking demonstrations and speakers from the food and farming industries as well as civic and spiritual leaders, including the Bishop of London were in attendance. The event aimed to highlight the work of FareShare in collecting surplus food from supermarkets and manufacturers and delivering it to homeless shelters and other community centres for society’s vulnerable. (Source:

Orchids and Fungi Partners for Life Three Thai orchids have been found to rely on a wide range of fungi to help them take carbon out of the soil instead of producing their own organic carbon. Aphyllorchis montana, A. caudata and Cephalanthera Aphyllorchis montana exigua orchids were studied. These orchids have no chlorophyll and rely on fungi colonizing their roots for their carbon supply. The plants were collected from 10 different sampling sites in diverse parts of Thailand. It was found that certain tropical orchids associate with highly diverse soil fungi colonizing their roots. All these fungi associate with the roots of nearby green trees, where they collect carbon for the orchids. Because plants interact with fungi in an unexpectedly diverse way, there is a great need for more research on biological interactions in the tropics to unravel this diversity. (Source:


MAXIMUM YIELD UK - March / April 2010

Dry Bread Thanks to Non-Leaking Tomatoes The first non-leaking tomatoes are now on sale at Tesco stores across the UK. The tomatoes are grown in Holland as part of a long-term seed breeding program that began in 1986. The breakthrough came last year after trialing more than 100 varieties through natural breeding methods. The breed held its shape when sliced, baked or diced. Tests also showed that, when making a sandwich from a standard tomato, eight per cent of its weight is lost after slicing it and a further 12 per cent of the moisture seeps into the bread only an hour later. With the non-leaking variety, less than one per cent moisture is lost when the tomato is sliced and only three per cent seeps into the bread in 12 hours after the sandwich is made. The new tomato is economical as tests have shown that you need around 30 per cent less than regular varieties when making a sauce. (Source:

High School Student Winner of Invent Your World Challenge The brilliant mind behind the invention of an algaepowered energy system is 15-year-old Javier FernándezHan. Combining a dozen technologies, the system treats waste, produces methane and bio-oil for fuel, produces food for humans and livestock, sequestered greenhouses and produces oxygen. As winner of the annual Invent Your World Challenge, Javier has been awarded a £12,260 scholarship, which will be used to build the project. The system consists of six subsystems, including an anaerobic digester for sewage and food scraps, a bio-gas upgrader to turn gases into food for the algae, a CO2-capturing device and much more. Javier would like to see the modular system targeted at developing countries that need self-contained sources of power and waste disposal. The excess methane could be sold for income, and thanks to the methane burning stoves, air pollution will be reduced. A scaled-down version of the system could be used for small houses or apartments that would cost as little as £120. (Source:

Buy Local…But According to the “Rough Guide to Green Living,” by Duncan Clark, while transport of goods accounts for a small proportion of the human impact on the climate, it’s not the only factor to consider. While it makes sense to favour local food and products, local is not always the best option. One study suggested that lamb from New Zealand, with its clean energy and rich pastures, has a lower footprint when consumed in the UK than locally produced lamb, despite the long-distance shipping. Another study showed that cut flowers sold in Britain that had been grown in distant but sunny Kenya had a smaller carbon footprint than those grown in heated greenhouses in Holland. The best option, as we know, is to grow our own all year round indoors. (Source:

Take An Item, Leave An Item Freegly With over 200 member communities and over 1 million people actively involved, I Love Freegle has become a popular spot for eco-conscious Britons eager to keep useful and reusable items out of landfills. I Love Freegle is democratically run and focuses entirely on the task of reducing landfill in the UK by people in the UK. All items and requests must be Free and Legal (aka Freegle). There are groups throughout all of UK - England, Wales, North Ireland and Scotland and each were created with no money. Many items have made homes in more than one member house. Freegle is creating more of a community than just a simple, online swap meet. Blog postings involve more than just items for sale, they also include green politics and green events. According to one Freegle group manager, over 30,000 furniture are taken to landfills every day in the UK. Freegle members are attempting to halt this eco-crime. (Source:

MAXIMUM YIELD UK - March / April 2010




hydroponic news, tips and trivia from around the world

EU Rules Lifted – Wonky Vegetables For Sale Fruits and vegetables previously deemed unfit for sale to consumers are now being accepted by grocers as 20year old EU rules are lifted. Marketing standards for 26 types of produce have been scrapped, in a drive to cut EU bureaucracy. The 26 types are: apricots, artichokes, asparagus, aubergines, avocadoes, beans, Brussels sprouts, carrots, cauliflowers, cherries, courgettes, cucumbers, cultivated mushrooms, garlic, hazelnuts in shell, headed cabbage, leeks, melons, onions, peas, plums, ribbed celery, spinach, walnuts in shell, water melons and witloof/chicory. Some 20 per cent of produce is rejected by shops across the EU because they are the wrong size or shape. With an appropriate label shops will be able to sell “ugly” specimens of the 10 most popular types of produce, which account for 75 per cent of EU fruit and vegetable trade: apples, citrus fruit, kiwi fruit, lettuces, peaches and nectarines, pears, strawberries, sweet peppers, table grapes and tomatoes. The quality of the produce will not be compromised. (Source:

Machines May Replace Humans to Inspect and Sort Strawberry Plants

A plant-sorting machine that uses computer vision and machine learning has been developed to inspect and grade harvested strawberry plants and then mechanically sort them by quality. Until now, these tasks could only be done manually. In field tests, the machine classified and sorted harvested plants more consistently and faster than workers could, with a comparable error rate. During the fall harvest season, strawberry plant nursery farms use manual labour to sort several hundred million strawberry plants into good and bad categories, a tedious and costly process. The machine will help farms improve quality, streamline production and deliver better plants to berry growers. The machine was tested under realistic conditions, where rain and frost change plants’ appearance, and roots may contain mud and debris. On average it sorted 5,000 plants per hour, several times faster than human sorting. The final system could be able to achieve sorting rates of 20,00030,000 plants per hour. (Source:


MAXIMUM YIELD UK - March / April 2010

Vermicomposting with Pig Manure? Researchers recently experimenting with pine bark amended with vermicompost derived from pig manure found that this organic alternative could produce healthy hibiscus. Reported benefits include greater plant growth and flower production, improved water use efficiency and sufficient levels of some plant-available nutrients. The purpose of the study was to determine if conventional nursery crop inputs could be replaced by commercially available vermicompost for hibiscus production. The research established that the vermicompost treatment did not supply potassium equivalent to conventional controlled release fertilizers. All treatments used equivalent volumes of water. The study suggests that dolomitic lime, sulphated micronutrients and phosphorous can be eliminated as substrate additives for hibiscus production. (Source:

Third “International Conference & Exhibition on Soilless Culture” (Singapore) The Third “International Conference & Exhibition on Soilless Culture – 2010” (ICESC-2010), will take place in Singapore March 8-13, 2010, with plans to host 500-800 researchers, growers and crop advisors from more than 60 countries. Also invited are serious health-conscious consumers, educators, suppliers, food processors, environmentalists, policy makers, property developers of eco-homes, potential investors and all environment-conscious people involved in “sustainable” food network in one way or another. The theme of this event is “Futuristic Environment-Friendly & Sustainable Farming Technologies for Growing Any Plants Anywhere” through hydroponics, organics and aquaponics. The aim of this event is to create awareness, exchange information and foster collaboration amongst the participants on the importance of soilless culture (hydroponics and organic farming techniques) in growing plants for food, ornamental, medicinal and industrial purposes. Please visit to learn more. This event is sponsored by the International Society for MY Horticultural Science (ISHS). MAXIMUM YIELD UK - March / April 2010


PRODUCT spotlight

See it. Want it. Find it at your local indoor gardening store. Introducing the Ozone Generator

HALO Growth Booster in New Soluble Sachets

The lightweight and CE approved Ozone Generator produces ozone using oxidation. Ozone will effectively eradicate bacteria from the air and surfaces. Bad odours and the spread of most diseases and contaminants come from the decomposing activity of bacteria microorganisms, which exist everywhere. Therefore, ozone generation is useful anywhere bad smells or hygiene standards pose a problem.

We all want more from our plants. Accelerated growth, early flowering, early fruit set, bigger yields and increased fruit set are all a must; all of this can be yours with HALO. HALO is the first product to use Harpin Alpha Beta protein – a powerful and natural new plant technology. After an easy spray-on foliar application of HALO, plants react like they are under attack and their natural defence systems are activated, resulting in a combination of physiological and biochemical reactions that activate plant growth and stress defence pathways. Scientific tests with NASA researchers have shown that HALO increases photosynthetic rates by 19.8 per cent after one day of application and over 25 per cent after four days of application. For healthier, more productive crops that can naturally fight disease, use HALO. Now available in five 2.5 gram/five millilitre soluble sachets making it even easier to use. Visit an indoor gardening retail store to learn more.

Features: • controlled ozone output with automatic shut off at predetermined ozone levels 50 mg/hr • extended ozone chip life • integrated circuit board • 220/240 volt 50/60 hertz system • unique ozone delivery system • timer controlled circuitry • constant volume of ozone • low maintenance • 12 months warranty Ask your local retailer to carry the Ozone Generator.

High Quality Hydroponics Fertilizer - Shiva A&B Cash Crop Shiva A&B is a two part, high quality, hydroponics fertilizer that is designed to be used in the grow and bloom cycle, in any medium (soil, hydroponics, coco peat). Shiva A&B are made from the most expensive and purest raw material, guaranteeing the fastest growth rates and heaviest yields. It’s simply the easiest to use and the best hydroponic nutrient on the market today. Since Shiva A&B are made from the best raw materials, they will never clog your vat, pump or irrigation system and the EC will always remain stable. Available in one litre, four litres, 10 litres and 20 litres. Ask for Shiva at your nearest hydro retailer. 14

MAXIMUM YIELD UK - March / April 2010

Xtreme Nutrients Root Tonic Root Tonic doubles root mass, which doubles your yield. It also prevents and cures wilt and all root diseases, and increases plant immunity and vigour for the highest yield potential. Commercial grade Root Tonic incorporates the newest technology from the latest research. With Root Tonic you get bigger yields every time. When you use Root Tonic, you are using a product that is the result of years of global research. It is the only product of its kind at the cutting edge of root protection and formation technology. The results of this research are now available to you for the first time ever. Root Tonic should be used throughout the entire growing and flowering process. Suitable for all hydroponics and soil plants. Visit an indoor gardening retailer to learn more.

New CANNAZYM Formula CANNA research has come up with an improved version of Cannazym. By increasing the concentration of the enzymes in the new formula, the activity of the enzyme on cellulose is increased while the response interval for function is decreased. Not only has the concentration changed, but shelf life has improved as well. Cannazym’s shelf life has been extended to 24 months and the product is better protected against cold temperatures. It simply works better for your plants. You can find the new Cannazym formula very soon in your local hydroponic shop.

Straightforward and Simple Sunleaves Ballasts Gardeners looking for reliable results from their HID lighting can look no further than the new Sunleaves Ballasts! The straightforward name highlights their easy operation, with headache-eliminating features like the common outlet and 120/240 volt dual-voltage capabilities. Choose from 400 and 1000 watt two-way (high pressure sodium and metal halide functionality in one ballast) and 600 and 1000 watt HPS options, all of which include a 120 volt power cord and a five-year manufacturer’s warranty. Ask your local retailer for Sunleaves Ballasts.

The Rock That Doesn’t Roll - Sunleaves Rocks Sunleaves Rocks are a reusable growing medium with serious H20-holding power for use in any kind of garden, and now gardeners can choose from two different sizes of this versatile growing medium! Both the small (0.5 to 1.2 centimetre) and large (1.2 to 3.8 centimetre) varieties are made by superheating shale to temperatures up to 1,100°C, rendering them pH-neutral and chemically inert. Gardeners can make their lives a little easier, take care of their plants and take it easy on the planet when they grow with the rock that doesn’t roll! Mined and manufactured in the United States. Ask for Sunleaves Rocks at your local hydro shop. MAXIMUM YIELD UK - March / April 2010


PRODUCT spotlight

See it. Want it. Find it at your favourite indoor gardening store.

Introducing Air Force 2 Silenced Fans This lightweight fan is easy to hang, extremely powerful and built into a silencer. The Air Force 2 works with all brands of speed controllers. Air movement and spigot sizes are as follows: Air Force 250 25 centimetre Spigot 1500 m³ Air Force 280 30 centimetre Spigot 2500 m³ Air Force 315 30 centimetre Spigot 3300 m³ Enjoy a free box of ducting with every fan purchase! Air Force 2 Silenced Fans are quality products in their build and design. In horticultural applications, these fans shift huge amounts of air for their spigot sizes and noise levels. Run to your nearest hydro shop to buy the new Air Force 2.

House & Garden Top Booster House & Garden Top Booster is an excellent flowering stimulator, which acts on the basis of potassium, phosphorus and Eddha-Fe (iron). These elements are important for the plant’s flowering; potassium for the beginning of the flowering stage and phosphorus for the proper development of fructification, while the Eddha-Fe additive ensures a better colouring of the leaves. Top Booster creates an optical drought giving the plant the impression that the last phase of its life cycle has started. To ensure its survival, the plant will then begin forming flowers and fruits to reproduce. Add Top Booster for two to three days and then return to the usual nutrient composition. The plant will continue to form fruits and flowers. As this aspect of the final phase of the plant’s cycle starts earlier, the fruits and flowers have more time to become larger. Never use Top Booster in combination with PK 13-14, Top Shooter or Shooting Powder. Top Booster is available now from your local hydroponics retailer.

Introducing Cobra from Cash Crop Cash Crop Cobra is a combination of many different beneficial bacteria and fungi species, which assist a plant’s growth by stimulating a massive root mass. Cobra also helps the plant tolerate extreme temperatures, nutrient imbalances and drought. Cobra contains 60 different strains of micro-organisms, 29 carefully selected beneficial fungi, nine endomycorrhizal, 11 ectomycorrhizal fungi and 19 strains of trichoderma bacteria. These microorganisms colonize the plant’s roots and stimulate the roots to grow into the surrounding medium, greatly enhancing the absorptive surface area of the root system and forming an essential link between plant and medium. Also included is a specially formulated root bio-stimulant, vitamins C and B1, kelp and humates. The plant will enjoy improved nutrient and water uptake and enhanced disease resistance. Cobra is the most effective high quality product in the marketplace today, creating an optimum growing medium and plant growth conditions. Visit your nearest hydro shop to learn more. 16

MAXIMUM YIELD UK - March / April 2010

Sunleaves Lightwave Reflectors Building on the design of the original Lightwave, new Sunleaves Lightwave Reflectors are the perfect choice for beginners looking to boost lighting efficiency. Their specular aluminium reflector bodies are ultra-lightweight and diffuse light evenly to eliminate hot spots. A great value for indoor gardening enthusiasts, the Lightwave Plug n’ Play is pre-wired with a fixed socket that’s compatible with the industry-standard common outlet, while the Lightwave CF Reflector is ideal for customers who want to take advantage of the money-saving benefits of compact fluorescent technology. The simple addition of a self-ballasted compact fluorescent lamp creates a complete self-contained lighting system! Sunleaves Lightwave Reflectors are available now at indoor gardening retailers everywhere.

Alaska Pure by Nutrifield® Alaska Pure is a complete flowering enhancer containing rich sources of potassium, natural plant growth hormones and 17 amino acids. It’s your ultimate organic potash. Potassium directly affects the production of chlorophyll while regulating stomata opening. This improves the plant’s ability to breath. Potassium is also an essential for the storage and movement of carbohydrates in plants. Carbohydrates are essential to produce higher brix (sugar) levels as to maximize the weight of your yield. Alaska Pure is an exceptional source of auxins, cytokinins and gibberellins. These all–natural hormones promote rapid cell division allowing the plant to uptake larger amounts of nutrient while improving its resistance to disease and pest infestation. Alaska Pure contains over 60 minerals with exceptionally high chelating ability. The unique formula also provides frost resistance and is able to deliver stress relief to unhealthy plants. Alaska Pure can be added to your reservoir with your nutrient solution or can be used as a foliar spray. For more information, please visit your local hydro retailer.

Fulife by Nutrifield® Fulife maximizes yields by improving your plants’ metabolic processes. It is derived from organic carbon allowing for faster growth due to improved photosynthesis. Fulife conditions soils and will improve stomata openings allowing for better plant respiration and transpiration, while helping the growth of beneficial micro-organisms. Fulife does not increase the salt index of your system. Therefore, there is little effect on osmotic potential (salt build-up) allowing the plants water uptake to remain unaffected. Fulife enables you to run significantly lower electrical conductivity (EC) without affecting nutrient absorption. Fulife is an organic electrolyte. Electrolytes are soluble particles that can effectively conduct an electrical current in liquid and plant substrates. The electrical activity serves to convert silica and metallic elements into easily absorbable plant food, while at the same time increasing the nutrient’s chelating speed. Plants respond by being able to take up previously unavailable elements leading to nutritionally satisfied healthy plants. For more information, please visit an indoor gardening retail store. Continued on page 48

MAXIMUM YIELD UK - March / April 2010


Your How-To Guide to Growing Irish Shamrocks

“The shamrock’s trefoil-shaped leaves mean it was a sacred plant of the ancient Druids of Ireland.”

For many gardeners, especially those who live in cold-weather climates, the weather can make gardening a bit of a challenge. Temperatures are starting to warm up, but there’s still a chill in the air. Sunlight will be in short supply for a few weeks longer. These elements combined with the hard, frozen soil add up to a difficult hobby—unless, of course, you do it indoors and your crop of choice is shamrocks. The name shamrock is derived from the Irish “seamrog” meaning “summer plant.” It is Ireland’s most famous symbol and represents the Cross and the Blessed Trinity. Its trefoilshaped leaves meant it was a sacred plant of the ancient Druids of Ireland and of other ancient civilizations around the world. The shamrock is forever connected to the teachings of the Three in One Trinity by St. Patrick in the fifth century and his banishment of serpents from Ireland. But not only Ireland stakes a claim; Montreal, Canada’s flag has a shamrock located in the lower right quadrant, proudly representing its Irish heritage. In addition, not many people realize that the shamrock is also a revered plant in the Muslim world.

The Auld Sod Company is offering the perfect gift for indoor gardeners. The Auld Sod Box Set is an all-in-one pack that lets the recipient grow authentic Irish Shamrocks in a beautifully crafted Belleek bowl with Official Irish Shamrock seeds. The box set includes: an exclusive handmade Belleek fine china bowl, official Irish shamrock seeds approved by the Irish Government and a one pound pouch of official Irish soil. Visit


MAXIMUM YIELD UK - March / April 2010

“Frequent misting… simulates rain, which shamrocks are well accustomed to in [their natural habitat].”

So how do you get started? K First, purchase some Irish shamrock seeds and place them in the refrigerator (not the freezer) for at least 24 hours. This tricks the seeds into thinking they have gone through a winter so they will germinate more quickly. K Select a pot or bowl to grow your shamrocks in and add your medium of choice - for real Irish shamrocks use authentic Irish soil - into the pot to a few centimetres below the rim. K Dampen the soil with water but do not overdo it (the extent of watering will depend on whether the pot or bowl has a drainage hole or not. For pots with no drainage you should water more sparingly; frequent misting is often best. K After 24 hours remove the seeds from the refrigerator, tear open and sprinkle evenly on the top of the damp soil. Real Irish shamrock seeds are actually coated in lime to add weight and to make them easier to see (without the lime coating they are virtually weightless and will be blown away by your breath). K Use as many of the seeds as you see fit. When you have done this, cover the seeds with a thin layer of soil and gently press down with the base of a glass or with your fingers. Moisten again and place in a bright location within the house but not in direct sunlight. K The seeds will germinate in a few days and seedlings will appear. They will grow quite quickly provided the soil is kept moist. We recommend frequent misting with occasional watering as the best method of maintaining the damp soil. This simulates rain, which shamrocks are well accustomed to in Ireland! K As the seedlings grow, you will notice that two leaves will appear. Have patience and faith, the third leaf of the trefoil will appear a few days after. The shamrock plants will turn toward the light source so try turning the pot the other way and watch the shamrocks twist. They actually move quite quickly. K The shamrocks will also fold their leaves up and go to sleep at night. The plants will continue growing for many weeks and will produce a yellow flower after about six to eight weeks. K When the plants become overgrown, cut them back with scissors, and if you keep the soil moist they will continue to grow. Call it the luck of the Irish, but the spring months represent the ideal time for the indoor growing of shamrocks. With St. Patrick’s Day this March, a shamrock will be ready for picking and wearing with pride for the celebration. MY

MAXIMUM YIELD UK - March / April 2010


Weird Plant Happenings by Dr. Lynette Morgan

Catface, epinasty, edema, vivipary, chimeras, mutants, shoestring growth - experienced growers often know what many of these terms mean and look like; to the rest of us they would fall into the category of ‘weird plant happenings.’ Sometimes plant growth does not progress as expected and strange symptoms can arise from a variety of causes that aren’t necessarily related to the grower’s actions in the grow room. Some unusual plant happenings are actually quite fascinating and completely natural occurrences, but others are just plain frustrating and best avoided. 20

MAXIMUM YIELD UK - March / April 2010

Lettuce and salad greens such as this chard plant can shoot upwards as they go to seed or `bolt,’ even at a relatively young stage.

Many variegated plants started out as a random mutation or chimera in standard all-green cultivars.

Common and frustrating or viviparous germination of seed, occurs weird plant happenings inside the fruit before it has been cut Many new growers often assume any open for eating. Mostly seen in tomato strange plant growth occurrence is due to a fruit purchased from the supermarket, it disease outbreak. In reality the truly weird has been known to occur in ripe fruit plant responses often have no connection while still attached to the plant. Cutting with pathogens. The most common weird open what looks like a normal tomato to symptoms experienced by new growers are discover a grotesque looking mass of twisted, caused by bolting, particularly with lettuce germinated seeds in the core of the fruit and other salad greens. Small or half-grown can be a little disgusting for those that are lettuce plants suddenly give up all hope unfamiliar; but, it doesn’t pose any risk if of forming a tight heart and rapidly spiral ingested.Vivipary occurs when the natural skywards into a type of ‘lettuce tree.’ Lettuce germination inhibitors surrounding the seed, plants that have fully bolted can become which are contained in the juice, break down, surprisingly tall, some over one metre, thus allowing the mature seed to germinate topped with a large developing flower head. inside the moist environment of the fruit This is a perfectly center. This strange “Weird plant happenings normal response to occurrence can range can be exciting and growth factors such from just one or two seeds potentially very profitable, as long, warm days, germinating inside the the newest cultivar just plant stress, root fruit, to many seeds that under your fingertips.″ disturbance and lack may even produce a small of nutrients, and is simply the plant’s attempt root system and seedling leaves while inside to reproduce before dying back. However, the fruit tissue. The cause of this problem is to growers unfamiliar with anything other usually temperature related. Fruit that has than a supermarket lettuce head, bolting can been chilled or exposed to prolonged cold come as quite a surprise. temperatures will break down the natural Vivipary is another odd incident that germination inhibitors in the fruit; when the occurs mostly in tomatoes. And although fruit warms, the seed may germinate.Vivipary common enough, can also be caused by the use of plant growth this condition can regulator compounds such as gibberellic acid, take people by which is used to assist fruit set under cool surprise; even the growing conditions. Some varieties are more most experienced prone to this problem than others, so it also growers.Vivipary, has a genetic nature. Vivipary inside a ripe tomato fruit – seeds germinating inside tomato flesh can be quite a shock to both consumers and growers.

MAXIMUM YIELD UK - March / April 2010


Weird Plant Happenings

A tomato plant showing a random genetic mutation causing foliage variegation – pretty, but not very productive.

Interesting and sometimes profitable happenings Sometimes weird plant happenings are exciting and potentially very profitable, if you know what to look for. Many of the variegated ornamental plants and some fruit varieties are the result of mutations, bud “Under high humidity, sports or chimeras. These roots or calluses can are caused by genetic sometimes be seen irregularities that occur in forming on the upper cells leading to permanent regions of the plant.″ changes, most common variegations in leaf tissue or even the production of albino plants. These genetic mutations can occur in all species and they can even be induced with the use of mutagenic agents. Many genetic mutations in plants are deleterious and don’t give any advantage or may even destroy the plant itself. Others have resulted in new clones of fruit and ornamental plants such as the Washington navel orange, which originated from a bud mutation of a standard orange tree. Mutations in fruiting plants which result in some desirable change to the fruit or growth habit of the plant are worth looking out for – the next exciting new cultivar could be under your fingertips. Variegated foliage suddenly occurring on an otherwise uniformly green plant is usually the result of a chimera. Many common species such as citrus, pelargonium, hydrangea, dahlia, coleus and many others have variegated cultivars, which were the result of a random chimera. Chimeras are plants composed of two or more genetically different tissues growing adjacent on the same plant – commonly seen as variegated foliage in patterns of green, white or yellow. These can be highly attractive and sought after in many species. If the chimera is stable, vegetative propagation will allow the variation to be carried over to many new plants. 22

MAXIMUM YIELD UK - March / April 2010

Natural plant happenings Bumpy stems, root nodes, split stems with calluses and masses of small roots, long thin roots growing from stems and other unnatural places – these are all symptoms of adventitious root formation and most are natural occurrences. Some plants, tomatoes in particular, and many climbing plants have the ability to form Root initials on the upper stem of a roots anywhere on the stem. This natural tomato plant, a natural adaptation allows new roots to develop occurrence which can appear rather weird if to anchor the plant and even take over these are numerous. from the main root system if necessary. However, new growers are sometimes taken by surprise when roots are seen developing above ground. While this is perfectly natural, with tomatoes it can be a symptom that all is not well in the root system and the plant may be responding to stresses such as root rot, low oxygen, over watering, cold root zone conditions and other damage. A more weird and less common root happening is when certain plant growth regulator sprays are used on cuttings or clones. Under high humidity roots or calluses can sometimes be seen forming on the upper regions of the plant, well above the rooting media. Weird things that should be avoided Catface is the term used to describe the sometimes ugly and very weird symptoms of tomato and other fruit when conditions are not optimal for fruit set and development. Tomato fruit can look as if they are turning themselves inside out with seed development on the outer surface of malformed

Many fruit irregularities result from less than ideal conditions during the early stages of development.

“Catface deformities typically occur in winter crops, a result of starting tomatoes too early in the season.″

Catface on young tomato fruit caused by low temperatures during pollination and fruit set.

and twisted fruit. Catface deformities typically occur in winter and early spring crops and growers who attempt to get tomato plants started too early in the season soon become familiar with this disorder. While catface is usually caused by low temperatures at the time of pollination and fruit set, it is also a symptom of hormone herbicide damage or certain viruses, in which case the foliage in the head of the plant will also be showing damage symptoms. Catface can be prevented by increasing temperatures and is usually only a problem on the first few trusses of early season crops. Virus diseases are another weird plant happening that are best avoided, although doing so is not necessarily that easy. While many of these symptoms can be caused by viruses, the most commonly seen is ‘filiform leaflets’ also known as ‘shoestring growth’ where growth in the head of the plant develops very thin, narrow, often thickened, twisted and sometimes purple growth. “'Shoestring growth' is seen as very thin, narrow, often thickened, twisted and sometimes purple growth on the head of the plant.″

Shoestring growth can be caused by either a virus infection or by contamination with hormone herbicides to which tomatoes are extremely sensitive.

Viruses can also cause strange colouring patterns, such as with the very common mosaic viruses, leaf curl, stunting and other fruit and plant symptoms.Viruses can be transmitted from plant to plant by the feeding of insects such as aphids, thrips, whitefly and other plant sucking pests, who are also responsible for bringing virus into crops. The tobacco mosaic virus can infect many species of plants as there are several strains and this can be spread through growers hands infected after handling cigarette tobacco. Other viruses can be seed borne and most can be transmitted from plant to plant via sap and by use of cloning. Any plant which is suspected of having a virus should be removed from the growing area and disposed of to prevent spread of the disease. MAXIMUM YIELD UK - March / April 2010


Cause and Effect

Weird Plant Happenings

Bolting – Small or half-grown lettuce plants form a tight heart and rapidly spiral skyward. Lettuce plants will be taller than average, topped with a large developing flower head. Cause: long, warm days, plant stress, root disturbance and lack of nutrients.

Weird leaf happenings Leaf roll is a weird plant happening that can have a number of different causes and in severe cases the whole plant can take on a rather startling appearance. Generally, however, leaf roll is restricted to either older leaves rolling and thickening or newer leaves cupping inwards. Older, mature leaves on fruiting plants which have become slightly thickened commonly roll somewhat when the plant is carrying a heavy crop load; this is often seen in tomatoes. Insufficient irrigation, high EC and high light levels as well as leaf age also increase the severity of this problem. If leaf roll is progressing up the plant on younger foliage, then the cause is often root disorders and root death. Cupping of new leaves in the head of the plant is most likely to be a mineral (calcium) deficiency which is Leaf roll is a common weird plant occurrence often environmental that can have many different causes. in nature since calcium is usually plentiful in most hydroponic nutrients. Increasing air flow and lowering humidity and EC help the plant take up more calcium and transport “'Ethylene is a plant hormone gas which can it up to the new cells occur naturally.″ developing in the growing point. Epinasty is another form of leaf roll, which is a little different and experienced growers soon learn to recognize this serious disorder. Epinasty is a downward bending of the leaves, similar to wilting; however, the leaves remain turgid. This is caused by a build up of the gas ethylene in the plant’s environment or root zone. Ethylene is a plant hormone gas which can occur naturally, as in the case of ripening fruit or when roots have become water logged. It can also be a contaminant of air heating systems burning fossil fuels under insufficient oxygen. Some plants such as tomatoes are very sensitive to ethylene and levels as low as 0.02 ppm can cause strange plant symptoms to develop that also include flower and fruit drop and severe leaf twisting and distortion. Another strange leaf happening is when foliage orientates itself to point directly upwards. While not that common in

Catface – Tomato fruit looks like it is turning inside out with seed development on the outer surface of the fruit. Cause: less than optimal conditions for fruit set and development due to growers attempting to start plants too early in the season. Epinasty – A downward bending of the leaves, similar to wilting, however, the leaves remain turgid. Cause: build up of ethylene in the plant’s environment or root zone. Tomatoes are particularly sensitive. Oedema – Green callus, puffy like growth on the upper and lower surfaces of leaves, which may rupture as they enlarge. Cause: the leaf tissue becomes waterlogged as a result of root pressure under high humidity conditions. Vivipary – Occurs mostly in tomatoes; the inside of the tomato contains a grotesque looking mass of twisted, germinated seeds in the core of the fruit. Cause: the natural germination inhibitors surrounding the seed break down, allowing the mature seed to germinate inside the moist environment of the fruit centre. It can also be caused by the use of plant growth regulator compounds such as gibberellic acid. Chimeras – Plants composed of two or more genetically different tissues grow adjacent on the same plant; commonly seen as variegated foliage in patterns of green, white or yellow. Cause: genetic mutations ShoEstring growth aka filiform leaflets - The growth in the head of the plant develops very thin, narrow, often thickened, twisted and sometimes purple growth. Cause: viruses transmitted from plant to plant by the feeding of insects such as aphids, thrips, whitefly and other plant sucking pests. 24

MAXIMUM YIELD UK - March / April 2010

“It can be quite spectacular to see a large greenhouse crop with all the foliage pointing upwards in an unnatural prayer to the sun.″

Cupping and tip burn of young foliage is often a localized calcium deficiency caused by environmental conditions.

indoor crops, it can be quite spectacular to see a large greenhouse crop with all the foliage pointing upwards in what appears to be an unnatural prayer to the sun. Under high light levels, young leaves attempt to prevent radiation damage by reducing

Leaf curl and thickening of older foliage on plants carrying a heavy fruit load under high light can be caused by starch build up and is a natural occurrence.

the amount of leaf area receiving light by pointing upwards. This is a good indication that overhead shade, thermal screens or a reduction in HID lighting is required. Oedema can occur in grow rooms and greenhouses under certain environmental conditions. This disorder causes green callus, ‘puffy’ like growths on the upper and lower surfaces of leaves. These puffy areas may rapture as they enlarge. Oedema develops when the leaf tissue becomes waterlogged as a result of root pressure under high humidity conditions. The roots pump water under pressure up into the plant; however, high humidity slows or prevents plants from loosing water via transpiration and oedema results because of this. This is more common when the nutrient or root zone is warmed, but the air is cooler. Lowering humidity and increasing air flow usually improves this condition rapidly, as does increasing the EC to restrict water uptake. Many weird plant happenings have similar symptoms so it can sometimes be difficult to determine exactly what is going on and the cause of the problem. Experienced growers soon build up a detailed knowledge of strange things they have seen before and most odd occurrences have been photographed and recorded somewhere at some stage. MY

Weird plants are popping up all over. Visit Online Extras to view less-thannormal, but still edible plants at

MAXIMUM YIELD UK - March / April 2010


Container Herbs for Beginners Increasingly, we’re being told that we can ‘green up’ our lifestyle by growing some of our own food. Articles everywhere suggest that everyone can grow a few herbs on the windowsill, but if you’ve never gardened before then that’s not as simple as it sounds. Here is a basic run down of what you’ll need, and what you’ll need to know, to grow some easy culinary herbs in pots. Firstly, you will need some containers. Herb plants are sold in small pots, which will quickly be outgrown. Look for some containers that are at least 15 centimetres in diameter (they don’t need to be huge). If they don’t have drainage holes in the bottom then you’ll need to punch some yourself. You’ll also need some compost – potting or multipurpose is fine for most herbs. Look out for composts that say they are peat-free. You won’t need a large bag to pot up a few herbs; your containers might have their volume printed on the bottom. If not, estimate how much compost you’ll need. Herbs can be divided into two main categories. Perennial herbs live for several years whilst for annual herbs you’ll need new plants each year. Perennial culinary herbs include thyme, mint, rosemary and oregano. There are many different varieties of each, but the most useful varieties will be widely available. For perennial plants it’s

by Emma Cooper

easiest to buy a small plant from the garden center and grow that on at home. Thyme is a low-growing plant that likes sunny and dry conditions. Rosemary likes the same things, but makes a much larger plant.You can get upright rosemary and prostrate (which grows down over the side of the pot), but the flavour is the same. And oregano is another herb in this group (known as Mediterranean herbs, because they like it sunny and dry) and also grows quite tall, but oregano is much less woody than rosemary. With all of these sun-loving herbs, you will need to water them to start with when you plant them into your pots. But once they show signs of new growth you can leave it longer between watering and let the compost dry out. Never leave them sitting in water, because they will rot. They are tough plants, but you may want to bring them under cover in wet weather. Mint is different, it can handle a lot more water and more shade than the Mediterranean herbs. It’s also a thug – keep it in a container by itself, because it will push out anything else that’s planted with it.

“The flavours in upright rosemary and prostrate are the same.”


MAXIMUM YIELD UK - March / April 2010

“Parsley is best sown in early spring for summer harvest, and will happily live indoors on the windowsill.” With just a little bit of care, perennial herbs will provide all the fresh leaves you need for several years. If they start to look too big for their pots, you can either pot them into bigger pots, or tip them out and divide them into sections and replant the sections into different pots – so you’ll have more plants for your garden, or to share. The cheapest way to grow annual herbs, like basil, coriander and parsley, is to buy some seeds and sow them yourself. If you sow them indoors, on the windowsill, the warmer conditions indoors will help them to germinate more quickly. Parsley is best sown early in the spring, for summer harvests, and in late summer for autumn and winter harvests. Parsley will happily live indoors on the windowsill, or outside on the patio. The seeds can take a few weeks to germinate, though, so be patient. One or two parsley plants should be enough at any one time. Parsley likes sunny spots, but more water than the Mediterranean herbs. Coriander likes warmer weather than parsley, so don’t put your plants outside until the weather has warmed up (usually May) or the cold will kill them. Keep harvesting leaves from your coriander, even if you don’t want to use them. Coriander runs to seed very quickly, and then the leaves taste bitter, but regular harvesting slows it down. Sow a pot of seeds every couple of weeks for a continuous supply throughout the summer. Bring a

couple of pots indoors if you want fresh coriander. Basil is a sun-loving herb, so don’t sow your seeds too early in the year unless the plants will be growing indoors – they don’t like cold weather. Keep your basil well watered, and harvest leaves even if you don’t use them, because (like coriander) this will stop the plants flowering too soon. When your annual herbs are flowering, put them and their used potting compost onto the compost heap and start again with fresh seeds and fresh compost – used potting compost has no plant nutrients left in it to feed new plants. If you don’t have a compost bin yet then it’s time to start one so that you can turn your plant and kitchen waste into home made compost to feed your herbs next year! MY

MAXIMUM YIELD UK - March / April 2010


“As a general rule, doing something that weakens your plants when they are already attacked by pathogens is not a bright idea.”

Fads and Fallacies

Growing plants in a closet, under artificial light is a relatively new activity. The utilization of hydroponic technologies in those closets is even more recent. This activity is often exercised by young people with no previous knowledge of plant growing and its related fields. Certainly not your typical greenhouse grower profile! As a result, there are numerous fads circulating in the home grower world that are deeply rooted in people’s mind. These fads are often propagated on Internet forums. Technical books on hydroponics are hard to read for most


MAXIMUM YIELD UK - March / April 2010

by William Texier - GHE

people without previous knowledge in chemistry and plant physiology. Many books on the subject of indoor growing cover your choices of system, lighting, ventilation, etc. Some of those books are well written and thorough but tend to be missing a detailed section on proper hydroponics practices. Some Internet forums cannot be trusted since manufacturers may use them to promote their products by posing as simple users, ranting and raving on how this product is miraculous. Others are good faith users that can, by like of experience, draw the wrong conclusions and propagate them; or it could

be something observed once and made as a rule without repetitive testing to verify what was observed! As a result, products are used improperly, causing damage when they could have been potentially useful. I will try to review some of them below.

Hydrogen Peroxide (H2O2)

Many companies sell H2O2 with the claim of miraculous effects, from improving the oxygen level in the nutrient solution to killing all pathogens on site. They often use anthropomorphic images such as: “the oxygen ion search for the bad guy.” Of course, there is some truth behind all that, but the presentation is rather misleading. When H2O2 is dissolved in water, it rapidly loses an oxygen atom that becomes a free radical. As you probably know, free radicals are extremely reactive oxygen ions. They have an electric charge and they attach themselves very easily to any other particle with an opposite

“Free radicals oxidize, or kill, spores and pathogens, but also root cells.”

charge. “Attach” in this case means oxidize, or kill. It is this same process that transforms iron into rust. All micro-organisms, as well as every living cell, have electrical activity, and thus attract a free oxygen ion...and die! The free radical does not have a selection mechanism that makes it target the bad guys. It will indiscriminately oxidize spores and pathogens, but also root cells. At the same time that it is cleaning the nutrient solution, it is weakening the plant. In fact, the quantity that you can introduce in the nutrient solution without killing your plant is so small that it is not enough to completely free the solution from pathogens. It is true that their population will be reduced, but they will rapidly come back in even greater numbers to attack the weakened plants. As a general principle, doing something that weakens your plants when they are already attacked by pathogens does not strike me as the brightest of ideas.

MAXIMUM YIELD UK - March / April 2010


Fads and Fallacies

The claim of extra oxygenation is also greatly exaggerated. It is important to realize that this ionic form of oxygen is not the one that the plant can use. Plants absorb O2, the gaseous oxygen that is in the air, the reunion of two oxygen atoms. What happens to that oxygen ion when it is released? Since it is very reactive, it will not live long, or travel far. It will, most likely, encounter something to attach to. It will then precipitate out of solution with that “something.” Once again, that can be a cell, a spore, but also a metallic ion such as iron. If some of those ions, obviously a small portion, manage to turn into gaseous oxygen, they will simply get out of the solution, at least for the larger part. The reason is simple: there is a maximum of dissolved oxygen that you can have in the water. This maximum varies mostly in relation with the temperature. Once that saturation in oxygen is attained, any extra would simply dissipate in the air. Granted, a minute fraction might be absorbed by the plant, but certainly not enough to make a difference. Don’t get me wrong, hydrogen peroxide is a very good product. There is nothing more efficient to rid a system from pathogens between two crops. I highly recommend the use of H2O2, especially if you experienced root problems in your previous crop. The use of a strongly acidic solution to dissolve the salts that might accumulate in the line, as well as using a strong solution

of H2O2 to get rid of pathogens should be your routine practice between crops. It is only the idea of using it with plants in the system that makes the hair on my neck curl backward!

CO2 Tabs

There is no doubt that bringing extra CO2 in the atmosphere surrounding your plants will improve their growth, their health and the yield of your crop. It is not easy to do when growing in a small space; the heat from the light forces a quasi-constant renewal of the air, making it less practical to introduce CO2. CO2 tabs serve a good purpose since they release in the growing space a large amount of CO2 in a short time. Therefore, it is possible to shut the ventilation down for just a little while, but not long enough for the air to become too hot. And this can be repeated a few times for more effect. However, it is a mistake to put the tabs in your nutrient tank. They must be dissolved in a separate bucket with no connection with your system.You simply do not want CO2 in your root zone! CO2 is a by-product of plant metabolism that is released by the roots in the nutrient solution, as well as some other molecules exuded by the plants. They are “polluting” the nutrient solution. A well designed hydroponics system works well for two reasons: it oxygenates the nutrient solution, but also, it helps dissipate the gazes out of the solution. CO2 tabs are absolutely counter-productive in the root zone. It is definitely a good idea to use them, but do use an extra container. Another good way to add CO2 is the slow release system that will bring a slow increase of CO2 at all times by means of a basic chemical reaction. This is practical, low-tech and efficient, and it will not pollute the nutrient solution. Both low-tech methods, if well used, can save you money.

Plant tissue at high magnification.


MAXIMUM YIELD UK - March / April 2010

“CO2 is a byproduct of plant metabolism and “pollutes” the nutrient solution.”


“Enzymes are

Most people are not familiar with the produced by bacteria, relationship between enzymes and bacteria. as part of their In fact the difference is pretty big: bacteria metabolism. They are alive, and enzymes are produced by are the weapons of bacteria, as part of their metabolism. They are bacteria.� the weapons of bacteria. Their role is to break down dead matter into single elements on which bacteria can feed. Enzymes are short lived but bacteria produce them all the time. Therefore, during a crop, if you introduce bacteria, it is like introducing millions of enzyme factories that are going to work for the duration of the crop. If well managed, it is obviously more efficient than introducing enzymes during the crop; at best, Bacillus bacteria it is a quick action that will not last very long. Enzymes are very useful when used properly, or in between crops, when you need to clean a substrate from the residues of tend to buy all the products on the shelf and hope that this will the previous crop and you want a quick, strong effect. In that help them succeed in their growing operation. In fact, it is often case, nothing works better than enzymes! For the rest of the the contrary. As strange as it might sound, I have seen many beginners fail just by doing too much. It is better to start with time, use bacteria or fungi (they are also enzyme factories). The the basics: a hydroponics system, a plant, a nutrient and a pH typical bacterium to use in this case is Trichoderma harzianum, corrector. This is all you really need. From there, you can start an especially efficient and economical product. experimenting with the many products on the market today, but We have seen with those few examples how useful products not before learning how to use them efficiently! can be detrimental when used improperly. Many beginners MY

MAXIMUM YIELD UK - March / April 2010


Wind, Earth, Water or Fire: Which

CO 2 Are You?

There is little debate over the fact that increasing carbon dioxide (CO2) levels in the growing environment will increase growth rates, give bigger yields and reduce overall cropping time. There is varying information on what levels are optimal in different growth phases, for the type of crop and even in varying nutrient programs. Carbon dioxide can be supplied with wind (fresh air), earth (natural fermentation or bio-activity), water (liquid CO2; compressed gas) or fire (gas fired CO2 generators). Each method of delivering CO2 to crops has its own unique qualities, capabilities and with some methods, even limitations.


MAXIMUM YIELD UK - March / April 2010

“The benefits attainable by supplementing CO2 levels… will largely be determined by how accurately the grower can maintain the levels.” Growers who want to have the most productive gardens and biggest yields will first take the time to create an optimal and controllable growing environment for their crop. Only then will the grower be able to realize their crop’s full potential with carbon dioxide enrichment. The benefits attainable by supplementing CO2 levels in the growing environment will largely be determined by how accurately and how steadily the grower can maintain the elevated levels of CO2. There are also practical considerations which include cost, level of skill required and the overall controllability of the existing growing environment. For the best results when supplementing carbon dioxide, the growing area should be able to function as “sealed” as possible. I have been discussing CEA (controlled environment agriculture) methods for many years now. In short, a “sealed” or “perfect” grow room has minimal to no outside air exchanges. The wind method of delivering CO2 to crops is found in traditional in/out style, mechanically vented gardens. By supplying a constant flow of fresh air through the canopy from outside air, then exhausting it out, CO2 is supplied at ambient (low) levels.

In this method, the highest levels of CO2 you can hope to achieve are ambient levels - the average CO2 level of outside air before it becomes depleted of CO2 by the crop for growth. Average ambient CO2 levels range from 350 to 650 ppm (parts per million). While this is sufficient to sustain average growth and flowering rates, for high yielding crops that produce at faster rate you will need more. To do so, the environment has to be enriched with additional levels of CO2. Enriched levels become defeated with constant air exchange as the CO2 is sucked out of the room (usually to ventilate heat away). This is why to achieve maximum yields with CO2 supplementation the grower needs to run a tighter or sealed environment. The easiest way to construct a CEA environment is to use an air-conditioner instead of a vent fan in the grow room for cooling purposes. There are specialty air conditioners available that are highly suited for use in grow rooms. Otherwise, simple air conditioners, even “window bangers” can be modified for use in a sealed growing environment with carbon dioxide supplementation. Besides being able to maintain higher and more precise levels of CO2 in the growing atmosphere, the grower will have precision control over the grow room’s most important parameter - temperature. To reduce electrical costs by cutting down on the frequency of cycling by the AC, growers can install or continue to use their air-cooled lighting systems. These still keep the environment “sealed” because the hot air removed by the reflectors from the lamps is sealed off from the growing environment by the protective glass. This helps to keep the additional CO2 in the room where it belongs, while removing heat from the largest source in the grow room - the lamps. If an air-conditioner isn’t possible, go with the air-cooled reflectors and a “smart” environmental controller, such as the unit featured in this article. This way, the exhaust fans won’t need to empty the air out of the room as often to evacuate heat when using air-cooled lighting. The air cooled shades will keep most of the heat out of the grow room. MAXIMUM YIELD UK - March / April 2010


Wind, Earth, Water or Fire: Which CO2 Are You?

the growing room is more productively filled with plants. For example in a one metre squared grow tent, you will need to devote about 25 per cent of your floor area to a fermentation bucket or carboy going the route of fermentation to boost CO2 levels. However, note that using LED lights to decrease ventilation requirements and a 22 litre primary fermentation tank in a one metre squared hydro hut allowed the author to achieve 2800 ppm of CO2 during the primary fermentation, which lasts just a few days. During the secondary fermentation, average levels were 900 ppm of CO2, lasting for about 10 days. There are some innovative products that use a natural This readout demonstrates that Earth methods of generating CO2 can be composting process to deliver small, but continuous amounts effective, although very difficult to control. These CO2 levels did not prove of CO2 to gardens. These can help to improve growth rates in to be excessive, although wasteful. The high readings were achieved during the primary fermentation of beer in an LED environment. smaller tightly sealed gardens. However, they are not controllable, The exhaust fan(s) will only cycle on when the temperature and do not produce large amounts of CO2 on demand. or humidity set-points are exceeded. The “smart” feature of the Most plants will not use carbon dioxide during the dark cycle, controller will stop your CO2 enrichment from running (tank/ so the CO2 generated through Earth methods is somewhat regulator or gas fired generator) wasted, although it is of no harm to plants to when the exhaust cycles, saving supply CO2 during the dark cycle. “Decomposition and fermentation produce carbon dioxide, and are you from wasting money Moving up the ranks of effective CO2 responsible for a portion of our generating valuable CO2 that is supplementation for bigger yields, we arrive ambient CO2 levels here on earth.” being exhausted out with the at water. For our purposes water will embody liquid carbon dioxide or compressed gas used hot air. This way, the air-cooled lighting will take away most of the heat, and the exhaust fan in CO2 supplementation. Typically, this is supplied by either 20 will need to cycle much less frequently, affording the grower a pound or 50 pound tanks that contain liquid CO2/compressed window to boost CO2 above ambient levels, greatly improving gas. The tanks alone will not provide the increased garden yields and growth rates. When the exhaust does cycle, you won’t performance levels that CO2 offers. be wasting valuable CO2 thanks to the integrated controller. If you choose to increase your yields and growth rates with So now that we have discussed wind, let’s move onto liquid/compressed CO2 tank, you will need a high quality earth. How does one get CO2 from earth? Well the truth is, “REG set-up,” which consists of a precision regulator/flow decomposition and fermentation produce carbon dioxide, gauge and an industrial solenoid valve. The unit featured in this and are responsible for a portion of our ambient article is of extremely high quality and is relatively inexpensive CO2 levels here on earth. While this method when comparing can produce some additional levels of CO2 to high-output in growing environments, it’s typically gas fired CO2 limited to being effective for very small generators. The flow scale gardens and less intensive growing rate is completely environments. adjustable and gives There is little or no control as to the grower a visual indication that there the level of CO2 that is produced and dispersed by these natural processes, and is pressure in the the output of CO2 will vary through the A high quality regulator and biological process producing the CO2. solenoid will show the flow rate of CO2 dispersed from To raise CO2 levels past ambient into the tanks in cubic metres per growth excelling 1000 to 2000 ppm range, hour. The little ball actually floats on the discharge of you will need a very tightly sealed environment gas to indicate the flow and will likely have to replenish your source of biorate. For smaller well sealed gardens, bottled CO2 is an carbon dioxide frequently. Also, to generate a significant and affordable and relatively safe sustained amount of CO2 for the crop, you will likely need a way to increase growth rates and yields. Be prepared to large volume of the bio-materials used to create the process in replace tanks frequently. the grow room. Unless you have boundless room, the space in 36

MAXIMUM YIELD UK - March / April 2010

tanks (you haven’t run out of gas) and indicates when the gas is If not enriching the growing environment flowing and at what rate. The little ball that floats in the set-up with elevated levels of tells you exactly at what rate the gas is leaving the tank; allowing CO2, growth will slow to a crawl if fresh air growers using timed CO2 to make more precise calculations. It’s containing ambient fun to watch too! CO2 levels are not kept moving across the foliage You will either need a timer that controls both the frequency during the light cycle. and duration of CO2 injections from the tank, or a carbon This HEPA filter helps remove contaminants dioxide level sensor/controller unit to activate the solenoid in from the fresh air entering the growing area. the REG set-up. The “smart” CO2 controller featured in this article allows growers not using infrared CO2 level monitors to dose CO2 into the growing atmosphere at controlled intervals look like missiles here and amounts. There are plenty of articles that describe how to and there. The cost perform the relatively simple calculations that will tell you how of adding CO2 to the growing environment much gas to release to achieve the desired CO2 ppm level in is highest using the growing atmosphere. The grower needs to know their flow rate, desired CO2 levels and the volume of the growing area. The bottled CO2 amongst wind, earth, water and calculation will tell the grower how long the CO2 needs to be fire methods described here. The initial equipment purchase emitted and how often (duration and frequency) Remember costs are moderate, especially if using a timed systems; it’s the that “smart” integrated controllers will shut off CO2 if exhaust frequent replacement of the heavy tanks that becomes costly systems are active; saving your CO2 for better use. and laborious. If you have never tried using If you run a sealed environment, CO2 in your garden before, a tank, good you will get the most out of “Bottled CO2 is heavier than most air quality REG and integrated controller are your CO2 set-up by controlling and can settle, so it needs to be kept an easy and less expensive way to give it CO2 levels with an infrared CO2 stirred and blowing across the plant’s leaves during the light cycle with fans.” a try. Look for a controller that can also monitor. This allows the grower accommodate an infrared ppm sensor so that to create exacting levels of CO2 when you are ready to upgrade, you can still use your existing in the plant environment efficiently, taking the guess work out equipment.Your plants will begin to grow at accelerated rates, of CO2 supplementation. Prices vary, and are dependent on so pay extra attention to your watering and feeding methods. the number of features and level of control you desire. Some As we move to fire in our CO2 enrichment hierarchy, consider units allow you to control more than one REG or generator fire to be a friend and beneficial elemental state, although not from the same unit (dual probes), while others may use “fuzzy to be toyed with or taken lightly. Gas-fired CO2 generators are logic” to improve efficiency. Always make sure that the unit you our fire in the scheme of yield boosting CO2 supplementation. choose can be serviced by the factory or place of purchase. CO2 To supplement CO2 levels in the growing environment, CO2 monitors are expensive precision instruments that may require generators or “burners” ignite fossil fuels such as natural gas re-calibration or fine-tuning from time to time. (NG) or propane (LP) to create a highly clean and efficient Overall, bottled CO2 gas is relatively safe to use; make sure you use the beverage grades and avoid welding grades as they contain combustion to burn oxygen out of the air and produce carbon dioxide in abundance as a result of the fire process. The impurities. The CO2 emitted from tanks adds no additional combustion also creates warmth and moisture in the air. In heat or significant humidity to the growing area versus gas fired sealed environments running with air-conditioners, the extra generators. The gas is relatively easy to disperse through the plant moisture in the air is welcome to help keep humidity levels at canopy. Simply connect one end of the specialty tubing supplied optimum, as ACs tend to de-humidify the air when operating. with your REG set-up to a strategically positioned oscillating In greenhouses or cooler months, the additional heat generated fan(s), and the other end to the REG set-up. Plug the REG into can be welcome, while in most situations it will require cooling your CO2 sensor, timer or integrated environmental controller, by AC. Cooling the growing area with exhaust fans defeats and your plants can begin to grow at accelerated rates and give fire as an efficient means to supplement CO2 levels for plant you bigger yields. Bottled CO2 released is heavier than most air growth; unless the exhaust fans cycle infrequently, including and can settle, so it needs to be kept stirred and blowing across when the burner is operating. the plant’s leaves during the light cycle with fans. CO2 burners have been around for some time and the newer Bottled CO2 works great for smaller well sealed grow models are quite safe to use when operated as specified by the areas with minimal air exchanges. It does require frequent replacement, which means lugging large heavy gas cylinders that manufacturer. Never use a NG burner on a LP supply or vice MAXIMUM YIELD UK - March / April 2010


Wind, Earth, Water or Fire: Which CO2 Are You? versa. When installing, inspect all Wind Earth Water Fire joints and lines for leaks by brushing N Y Y Y able to increase CO2 above ambient levels N N Y Y CO2 output is controllable and sustainable with a soapy solution and looking low low moderate moderate to high relative cost to install for air bubbles. Always keep propane low low to moderate high moderate relative cost to run tanks outdoors, and not inside. Long creates additional heat N N N Y hoses are available to supply burners relative yield increases low moderate high high from tanks outdoors. A high quality CO2 burner, such as the one featured in this burners like the one pictured in this article have oxygen sensors, article, is recommended. The first generation(s) of CO2 burners tip-over shut-offs and many other features that allow them to be helped early growers get bigger yields. However, by today’s used in closed environments with a relative level of safety. standards, they are fire-breathing dragons of yore. Modern CO2 The flame produced by high quality specialty CO2 generators burners use electronic ignition systems instead of standing pilot is pure blue, indicating that few impurities will be released with lights. This saves on gas used for combustion, and creates an the CO2 during combustion. Flickers of orange or yellow in additional level of safety. Do not use just any source of flame to the flame indicates the combustion process is inefficient, and try and create CO2 in your growing environment. The results may produce gases like carbon monoxide (CO), which can be very harmful or even deadly to you. If combustion is “dirty” or could be deadly; you are literally playing with fire. Modern CO2 inefficient, ethylene gas may be produced, and just a few ppms of it can harm or kill your crop. For some growers, using water-cooled heat exchangers in conjunction with their CO2 burners helps to reduce cooling requirements in the growing area associated with the extra heat generated during combustion to produce CO2.They tend to run through quite a bit of water for cooling in a drain to waste cooling system, or require large volumes of water and tanks that need to be cooled if you are running a “closed” liquid cooling system. For the most efficient and trouble free CO2 enrichment setup, a high quality CO2 burner and infrared monitor/controller is recommended if you are gardening on any kind of scale. While fire is not the least expensive route to take, once set-up and installed, you will just need to refill the propane tank (kept outdoors) occasionally. Better yet, if you have natural gas available to you, buy a NG gas CO2 burner, and have a qualified technician install a gas supply directly to the burner that has an on/off valve Modern and well constructed gas fired CO2 generators are designed in the supply for safety. From there, all you will need to do is try for use in grow rooms. Always and keep up with the accelerated growth rates of your crop! use a high quality model, such as the one featured and follow So, what kind of CO2 do you rely on to help determine your the manufacturer’s installation yield levels? If you are at the wind level, consider moving up to recommendations to the letter to ensure safe and trouble-free earth or water; you will notice a big difference in your rate of operation while boosting growth production. If you are a professional, or even a hobbyist looking rates and yields. to get bigger yields and reduce cropping times, fine-tune or upgrade your set-up to the water or fire level; once you have, you will never look back. Remember that to get all the benefits associated with elevated CO2 levels, all of the parameters in your grow should be at optimal levels first. As you start to incorporate CO2 into your game, take the time and possibly even a little extra expense to do it right. This way, all you are left to do is to try and keep up with accelerated growth rates that can drive your crop to bigger yields. MY Combustion is an efficient means to elevate and control carbon dioxide levels in larger grow rooms. Notice how blue the flame is. This signifies a clean and efficient combustion, producing plant usable CO2 without other dangerous gases that appear as yellow or orange flames.


MAXIMUM YIELD UK - March / April 2010

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Micropropagation The culture of tissue

by Brian Johns When I first learned of micropropagation (or tissue culture) all I could think of were men and women in white coats working inside a high-tech laboratory. In fact, my perception of micropropagation and its seeming complexities kept me from even researching the subject for some time. Fortunately, my curiosity eventually outweighed my intimidation. For those of you that don’t know, micropropagation is the practice of rapidly multiplying stock plant material to produce a large number of progeny (offspring) plants using modern tissue culture methods. In fact, for those of you who are familiar with cloning/cutting methods of plant duplication, micropropagation is very similar with some very distinct advantages: 40

MAXIMUM YIELD UK - March / April 2010

• Faster propagation (10 times faster than most methods) • No worries about fungus, pests, etc. • Long term maintenance of plants (if need be, you can just stick them in the fridge) • Identical clones of horticultural varieties easily generated (keep in mind that the integrity of clones is influenced by stress factors, genotype, culture age, cutting and transferring technique and contaminant levels)

"many of the prepared grow mediums are plant specific, which means they contain all of the appropriate minerals, nutrients and hormones needed for your specific plant." How to get started: There is one point that I cannot stress enough before you begin – maintain cleanliness! All other factors in micropropagation are important but none of them will affect your results as much as this one. What are the basic steps of micropropagation? 1. Select a plant from which to take tissue samples. It is important that your plant be free from any visible signs of disease or infestation. Typically, plants that are grown indoors are more successfully micropropagated than those grown outdoors simply due to lower levels of contaminates. It is also important to sterilize your plant as much as possible. Wipe the plant down with a mild bleach or hydrogen peroxide solution (approximately 2.5 grams per litre). 2. Select the appropriate containers in which you will be placing your grow medium and tissue cultures. This can be something as simple as baby food jars. I recommend small mason jars because they are glass (easily sterilized); you do not have to remove any labels (labels block the plants from receiving light and you don’t want that); the lids can be easily adjusted to accommodate more or less airflow; and they are readily available and inexpensive. 3. Prepare your grow medium. There are many different forms of tissue culture grow mediums on the market today. The advantage of purchasing a prepared grow medium is that it takes a lot of the guesswork out of the process. Also many of the prepared grow mediums are plant specific, which means they contain all of the appropriate minerals, nutrients and hormones needed for your specific plant.

Modern micropropagation lab by Terra Nova Nurseries.

(Note: Prepared grow mediums are only partially prepared as there is some mixing involved).You also have the option to mix your own grow medium. 4. Take cuttings from your plant and place them into the grow medium. The best way to do this is with a scalpel and tweezers that have been sterilized. As it pertains to what sections of the plant to take your cuttings from, this is one area where you get to experiment a little bit. With some plants, even sections of the leaf tissue will root and form clones, so be creative and take samples from various locations of your plant and keep track of which cuttings work best. It is important to think small when taking your cuttings. All that is needed is 0.4 to 2.4 centimetres of plant material. 5. Now you have your grow medium and cuttings in sterilized jars with the lids loosely on top. Place the jars approximately 30 centimetres underneath cool spectrum fluorescent lighting. The temperature should be kept between 15°C to 24°C. Light cycles can be kept consistent with vegetative plant light cycles (16+ hours of light per day). The area in which you store/grow your clones should have little to no air circulation, as to reduce the risk of contamination. 6.In a very short period of time you will begin to see your plants take shape and begin to resemble adolescent plants as opposed to chunks of plant material. At this point you have a couple options: a. You can continue to grow your plants with the same method, transplanting them into larger containers as needed. Once your plants have quadrupled in size you can actually divide them into pieces and start the process over. b. You can place your plants into soil or a hydroponic growing medium. The key to success in transferring your plants from the micropropagation growing medium to any other growing medium is ensuring that you have removed all of the micropropagation medium prior to transplanting. Also you should treat these small plants with as much care as possible until they have been assimilated to their new environment (placing a humidity tent over them and diffusing their lighting is highly recommended for the first week after transplantation).

Tissue cultures growing in mason jars Atlanta Botanical Gardens.

MAXIMUM YIELD UK - March / April 2010


Micropropagation: The Culture of Tissue

"it cannot be stressed enough that cleanliness and sterility are of utmost importance."

Again, it cannot be stressed enough that cleanliness and sterility are of utmost importance. From the instruments that you use to the area in which you take the cuttings from your plants, your success will depend on how well you are able to protect these small plants and limit their exposure to contaminants. After reading all of this you are probably wondering why you would even bother with micropropagation. Let me give you a real life example as to why this method can be so valuable. If you were to take a tomato plant that has been in a vegetative growth stage for approximately eight weeks, using standard propagation techniques (cloning/cutting) you would be able to get from 100 to150 clones Sterilized mason jars from that one plant. Now, 42

MAXIMUM YIELD UK - March / April 2010

if you were to take that same plant and apply the principles of micropropagation and tissue culture to create your clones you would end up with 1,200 to 1,800 clones from the same plant. That’s an impressive and exponential leap. In cases with rare or heirloom varieties of plants where seed stock is limited, micropropagation and tissue culture become viable and even preferred alternatives to standard methods of propagation. Now, what I’ve provided are some very rudimentary and basic guidelines for micropropagation, so I highly encourage you to do some investigation on the subject for yourself. The problem that most people run into as they begin to study micropropagation and tissue culture is that the bulk of the information that exists on the subject is written in highly scientific language that can be difficult to understand. To aid you in your research, however, I have compiled what I believe to be some of the best information and most relevant links on the subject. If I could only have one book on micropropagation it would be Plants from Test Tubes by Lydiane Kyte and John G. Kleyn. I also recommend taking a look at Google’s online library. The majority of the textbooks that exist on this subject are available there. Although they may be a little bit more difficult to understand and apply, they do have some very valuable information. Websites: This website is dedicated to educating people about the advantages of tissue culture. They also have a great selection of tissue culture supplies that are available for purchase. This is a good source for tissue culture supplies. Not to mention, they have a considerable amount of information for free on their website. This is another good source for tissue culture supplies and information. Additionally, I recommend visiting and searching for “micropropagation” and “tissue culture.” They have quite a few videos on the subject that I have found to be very beneficial. The videos help to clarify some of the information that you will find in print – an excellent learning tool. MY A simple grow medium recipe is available exclusively on



1 2 3

4 5 6

The name shamrock is derived from the Irish “seamrog” meaning “summer plant.”

With some plants, even sections of a leaf tissue will root and form clones. Also, it is important to think small when taking cuttings.

Metabolizing proteins release amines and sulphurcontaining organic molecules into nutrient solution. Microbial growth in the nutrient is a result of having organic materials in the system.

7 8 9

Leeching nutrients from mother plants three days prior to taking cuttings will improve the health and vigour of the clones.

All micro-organisms and every living cell have an electrical activity and are susceptible to attract a free oxygen ion.

The calculation of flow rate, desired CO2 levels and the volume of the growing area will tell the grower how long CO2 needs to be emitted and how often.

A tomato that looks as if it is turning into itself with seed development on the outer surface of the malformed and twisted fruit is known as catface.

Mint should be kept in a container by itself, as it will push out anything else that’s planted with it.

The flame produced by quality, specialty CO2 generators is pure blue, indicating that few impurities will be released with the CO2 during combustion.

MAXIMUM YIELD UK - March / April 2010



Simon Atkinson of Easy Grow, manufacturers of food and plant grade foils, examines how Easy Grow foils can assist with plant growth. Maximum Yield (MY) How many of your foils are food and plant safe? How are you able to guarantee that? Simon Atkinson: All of the Easy Grow foils are produced with food/plant grade materials and are certified to food grade standards to prevent harmful toxins or gases from being generated when in contact with strong heat sources. Easy Grow Ltd. guarantees this, as our core business is the supply of printed and plain laminated packaging products to the food industry. Our foils are formed into pouches and used to retain the temperature of frozen food goods in transit, which is critical to the success of the companies we work with.


MAXIMUM YIELD UK - March / April 2010

Simon Atkinson

MY: What are the differences between your various foil products and how does each type work uniquely? Simon: We have a wide range of foil products, which vary from the standard original black/white (panda sheeting) supplied up to eight metres wide by 25 metres long, to our high grade specification, diamond diffusion lightite foil. Our white lightite foil is manufactured as a three layered sheet, which is white on the outside and a layer of high quality black polymer sandwiched in the middle; this allows light to be reflected from both sides, with the middle black layer blocking light to allow separate light cycles to perform within the same area. Our metalized silver foils are available in two grades: eco and lightite. The lightite range in silver/white and diamond diffusion, as the brand name states, are light proof products, which have the ability to reflect up to 96 per cent of the light/lumens in the grow room, whilst being 100 per cent light proof and having the capability to also retain the heat/thermals produced within the grow area, due to its five layered construction. The eco range of silver/white and diamond diffusion were created to offer a competitive alternative to the range of poor quality non food grade foils that appeared in Europe four to five years ago. Both the lightite and eco ranges are produced with food grade materials and are PET coated to protect against corrosion and wear.

MY: What various jobs can your foils accomplish in the grow room and how does the new grower go about installing them? Simon: Our diamond diffusion foil was created to spread light more evenly, to help eliminate hot spots in the grow area, which was a concern for our customers, whilst using artificial lighting over long periods of time. The diamond embossed pattern also reduces creasing, a problem often associated with thin, poor quality reflective materials. We also sell a very popular product called “floor secure� in Europe, which is produced with a white material, four metres by 25 metres and 12 millimetres thick. This was created to save growers the worry of water damage, the non-ripping heavy duty product will secure any floor and give growers ultimate peace of mind. All foil products we supply can be installed with a good quality tack/staple gun or a heavy duty gaffer/duck tape.

MY: What are the benefits of your foils in the grow room? Simon: Using Easy Grow foils in the grow room gives an increased yield, as more light is returned to the actual plant/ growing area, allowing bigger/weightier plants to develop. This allows for a reduction in the actual amount of lights required in the same area, thus reducing the electrical costs and helping reduce the carbon emissions used in the indoor growing cycle. One of the main reason Easy Grow foils have been so successful is our customers know our trademark; every metre of our foils is a guaranteed quality food/plant product, which only enhances and increases the quality and yield of the chosen crops. MY: How many growing cycles does one application of foil last for and how does the grower dispose of it? Simon: We suggest a new application of foil is applied to the growing area every six to 12 months, although some of our customers tell us by replacing the foils on each new grow (as some growers do with light bulbs), have found this creates up to 15 per cent greater yield per plant. MY

If you would like to have your product featured in "You Tell Us," please contact or give us a call at 250 729 2677

MAXIMUM YIELD UK - March / April 2010


by Matt LeBannister

With so many different varieties of plants available to the home gardener it is no wonder that people want to preserve their favourite strains. Gardeners can replicate all the traits that made a particular strain their favourite through cloning. A clone will have the same genetic make-up and sex as the “mother” or “parent” plant they were taken from. If you have a chili pepper plant that delivers a high yield, is resistant to insects or thrives in the particular climate you are growing in, these traits are worth preserving. Cloning also saves the grower time since they do not have to determine the sex of the plant and because clones mature faster than seeds. This equals a faster crop rotation and more crops per annum. The way to get the best clones is to take them from healthy, strong mother plants.

“Clones taken from plants that are too young or too old will be weak and will bare fewer fruit or vegetables.” When selecting a clone or seedling to become a mother plant there are some rules to keep in mind; when first choosing a new parent plant one should always sacrifice the strongest and healthiest clone or seedling because their vigour will be passed along to the next generation of clones. The stronger a plant, the faster it grows, the more it produces and the less chance it has of being affected by disease or insects. 46

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Once the future mother plants have been selected they should be segregated from the rest of the plants.This will hopefully ensure that any outbreak of insects or disease amongst the general population of plants will not reach the mother plants. Any gardener who has lost their favourite strain to bugs or disease will tell you that this simple precaution will protect years of hard work. Once separated from the rest of the population, mother plants should be kept in the grow phase. Clones can be taken from plants that are flowering but they will not root easily and, therefore, it is not recommended. Eighteen hours of uninterrupted light and six hours of uninterrupted darkness is recommended although some gardeners will leave the lights on 24 hours a day. To improve the overall health and vigour of the mother plants only feed them premium grow-phase nutrients. Mother plants should be at least two months old before clones are taken and should be replaced once they are two years old to ensure clones taken are as healthy as possible. Clones taken from plants that are too young or too old will be weak and will bare fewer fruit or vegetables. Leeching nutrients from the mother plants three days prior to cuttings being taken will also improve the health and vigour of the clones. Clones root quicker with no nitrogen in their system. When there are no nutrients present the clone is forced to grow strong roots in order to search for nutrients. The health of the mother plant is so important because it directly reflects the health of the next generation of clones. Healthy plants mean less time, less trouble, better yields and MY more rewarding experiences for gardeners.

MAXIMUM YIELD UK - March / April 2010


PRODUCT spotlight

See it. Want it. Find it at your favourite indoor gardening store.

Continued from page 17

House & Garden Algen Extract Algen Extract is a concentrated solution of Norwegian Sea Kelp (Ascophyllum nodosum). Plants in all phases love kelp for the many benefits it provides. Micronutrients, microbiology and macronutrients are all present in Algen Extract. Algen Extract growth stimulator is a product designed for use with sprouts that have rooted well. It ensures better leaf colour and stimulates the formation of root hair, leading to increased uptake of various trace elements. Great as a foliar spray and for root applications. It can also be used as a leaf wash in case of chemical pest control and dusting. Algen Extract is available from hydroponic retail stores.

House & Garden MultiZyme House & Garden MultiZyme is an extremely useful growth stimulator that accelerates and simplifies the growth process and strengthens the plant’s immunity. The enzymes convert the nutrient into ready-to-use bits making it easy to assimilate by the plant. MultiZyme is a collective term for a wide range of useful enzymes, which are very important for plant processes and processes in the environment. They are small catalysts that trigger these processes and keep them running. There are enzymes that help to convert the plant’s nutrients, strengthen plants’ immune systems and help to dispose of residuals in the substrate. Use MultiZyme during the first three weeks of flowering. MultiZyme is available now from your local hydroponics retailer.

Sugar Peak Do you demand a feed that has the best of mineral nutrition with golden nuggets of guano, sea kelp and other organic material all mixed together? Well Sugar Peak has it all. Sugar Peak is a unique blend of selected natural organic elements, bio-enhancers with the purest elemental nutrient complexes. Comprising of a range of feeds that takes care of the plant’s precise requirements throughout the growth cycle, the Sugar Peak range includes: 1. Sugar Peak Leaf Growth 2. Sugar Peak Flowering 3. Sugar Peak Grand Finale 4. Sugar Peak Briximus Maximus 5. Sugar Peak Catalyst – general booster Not only does it feed plants, Sugar Peak also inhibits excessive bolting growth, decreases insect attacks and induces auxin exchange. Developed for plants grown hydroponically, in soil and coco coir, Sugar Peak is for the grower who demands the best without the hassle. Ask your local hydro dealer to stock this product.

Non-Dangerous pH Up and Down by Flairform - Now Available pH Up and Down have traditionally been the most dangerous chemicals in the hydroponic industry. Flairform’s non-corrosive pH Up and Down provide the first and most effective alternative to this problem. • Equivalent working strength to most corrosive formulations. • Safer to use. • Easier to use: overdosing won’t drive pH to extremes; great for novice growers! • More environmentally friendly. • Simplifies freight and storage - transport by air, road or sea is unregulated. Why trust a backyard chemist? Flairform: Analytical Chemists and Horticultural Consultants Since 1966. Ask for the new pH Up and Down from an indoor gardening retail store.

MY You can find all of our products online at Each month your favourite new product profiles will be featured on our website. Get the latest information on what will make your garden grow. Do you want to be included in the product spotlight? Contact the editor at 1-250-279-2677 or email


MAXIMUM YIELD UK - March / April 2010

CHECK YOUR growing I.Q.

by Erik Biksa


1. Which of the following are effective in chelating nutrients of absorption in crops? a) EDTA b) DTPA c) EDDHA d) Protienates e) Fulvic Acid 2. Ultra-tough question: Which amino acid is arguably the most effective chelate? 3. Which of the following are not B vitamins: a) Thiamine b) Hydrochloride c) Cobalamin d) Niacin

4. In which of the following product types is it most effective to have the smallest molecule size? a) Fulvic Acid b) Phosphorous c) Enzymes d) None of the above 5. In a soil/soilless media would it be best to: a) Flush with a large volume of water or leeching solution over a short duration during the final phase before harvest. b) Flush with smaller volumes of water or leeching solution over a longer duration during the final phase before harvest.


6. Based on your choice for the above answer, why?

ANSWERS: January/February 2010 quiz

1) b, 2) pH 5.5, 3) pH 6.5 4) Every medium requires special consideration to pH depending on it's inherent property of being inert or non-inert. Non-inert media (coir) will interact with the amount of available nutrient pH. Inert media (rockwool) does not interact at all. 5) a, 6) b, answers to this quiz will be printed in the May/June 2010 issue of Maximum Yield. MAXIMUM YIELD UK - March / April 2010


COMINGmay-june UP IN2010

Stop Hydroponic Odours Keep your hydro system clean and smelling fresh with these six simple tips.

Bigger Yields What has worked for others can work for you too! Growing secrets from the author will help you cultivate the very best.

Winter Watercolours Orchids in bloom liven up any home or indoor garden with colour and beauty. A proper watering regime, exact lighting and temperature plus the proper blend of nutrients is the key. Upcoming international events, exclusive contests, latest industry news, reader question and answer, best products and technologies, and much, much more. Maximum Yield May/June will be available May 1 for

FREE at selected indoor gardening retail stores across the UK and on Subscriptions are available at


MAXIMUM YIELD UK - March / April 2010

Maximum Yield UK - March/April 2010  

Hydroponics gardening resources by Maximum Yield, a free how-to hydroponics gardening and indoor gardening bi-monthly magazine that is distr...

Maximum Yield UK - March/April 2010  

Hydroponics gardening resources by Maximum Yield, a free how-to hydroponics gardening and indoor gardening bi-monthly magazine that is distr...