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july 24-25

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VOLUME 10 – NUMBER 2 July/August 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

If you plan on travelling to just one destination this year, head to California, USA for one of two major events planned for the indoor gardening industry. Join us in San Francisco, CA July 24-25 for 7th Annual Indoor Gardening Expo, aka the biggest expo on the planet, stop in Long Beach, CA October 16-17 or better yet, attend both.

Visit www.indoorgardeningexpo.com to full event details.

Win BIG! Grow BIG! We’re thrilled to announce a new giveaway to win gear to help you grow. Full prize details are available at www.maximumyield.com/winbigUK . To be chosen as one of four lucky winners enter by August 15, 2010 before midnight.

PRESIDENT/PUBLISHER - Jim Jesson GENERAL MANAGER - Don Moores BUSINESS MANAGER - Linda Jesson SALES DIRECTOR - Lisa Lambersek EDITOR - Jessica Raymond jessica@maximumyield.com ADVERTISING SALES 250.729.2677 Linda Jesson - linda@maximumyield.com Lisa Lambersek - lisa@maximumyield.com Ilona Hawser - ilona@maximumyield.com Gaby Morin - gaby@maximumyield.com Ashley Heppell - ashley@maximumyield.com PRODUCTION & DESIGN ads@ads.maximumyield.com Alice Joe - alice@maximumyield.com Wes Cargill - wes@maximumyield.com Daniel Peters - daniel@maximumyield.com ACCOUNTING - Lee Anne Veres leeanne@maximumyield.com

Get in the Know Are you a subscriber to Maximum Yield’s E-News? You should be, and here’s why: Every month, Maximum Yield mails out our free newsletter full of the latest news, grow tips and upcoming events and more. Enter at http://maximumyield.com/newsletter.php today and get in the know.

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Tell us what you think at editor@maximumyield.com. 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 www.suntec.co.nz/consultants.htm and www.suntec.co.nz/books.htm for more information.

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.

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.

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MAXIMUM YIELD UK - July / August 2010

Jose Luis Pinheiro Bartolo is the president of Biobizz Worldwide Inc., a global leader in the production of hydroponic organic fertilizers and soil mixtures. He is passionate about the organic market and providing the highest service and perfectionism that comes direct from his heart and is projected to all aspects of his life.

Noucetta Kehdi is the co-founder and

administrator of General Hydroponics in Europe. Noucetta got involved in hydroponics in the early 1990s and in 1996 she moved to the southwest of France where she takes care of a greenhouse educating herself on all things hydroponics.

Philip McIntosh is a science and technology writer with a bachelor’s degree in botany and chemistry and a master’s degree in biological science. During his graduate research he used hydroponic techniques to grow axenic plants. He lives in Colorado Springs, CO. where he teaches mathematics at Challenger Middle School.

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 july / august 2010 FEATURES 18

Growing Up: Tower and Vertical Systems for Small Spaces

by Dr. Lynette Morgan

24 24

22

Biostimulants: What are they and how do they work?

by Luis Bartolo

24

Growing Root Vegetables in Hydroponics

28

Next Generation LEDs: Enter the Quad Band

by Peggy Bradley

by Erik Biksa

28

34

34

Viruses in Hydroponic Plants

38

Growing Globally: Hydroponics in the Wild Wild East

42

Preventing and Reacting to Green Algae

44

by Philip McIntosh

by Noucetta Kehdi

by Matt LeBannister

DEPARTMENTS 4

Maximum Yield.com

6

From the Editor

6

Letters to the Editor

8

Ask Erik

38

10

MAX Facts

14

Product Spotlight

40

Talking Shop

43

Do You Know?

44

You Tell Us

49

Check Your Growing IQ

50

Coming up in September - Octorber MAXIMUM YIELD UK - July / August 2010

5

FROM THE editor

jessica raymond

Summer holidays are so near you imagine the office floor has transformed into hot, white sand and your coffee has become a margarita as you bask under the bright sun, aka indoor lighting. But before you hop a jet to an all-inclusive, make sure your prized crops are taken care of. If you’ve opted for an automated set-up, you can fairly easily step aside and let it do what it’s programmed for. Controllers, slow release biological stimulants and timed lighting are your friends when vacation time rolls around. That doesn’t mean you can simply press power and take off, but it makes caretaking much simpler

for your neighbours or friends that have agreed to plant sit. And if they find themselves struggling, tell them to send their questions to Simon Hart, Maximum Yield’s new resident expert, at Simon@maximumyield.com and their troubles may just disappear.

Now that all is settled in the grow room, you can breathe easy, fashion your sweet new shades and settle into the window seat with the latest copy of Maximum Yield UK. Enjoy.

Maximum Yield Now on Your Smartphone!

Connect to MaximumYield.com instantly from your Smartphone with our all-new Quick Response (QR) Code, found on the cover of every issue of Maximum Yield.

Now you can access the best products, the most in-depth articles and information and the latest news at high speeds. Simply download your choice of QR software to your Smartphone, scan the QR Code and your phone’s browser will automatically launch, redirecting you to www.maximumyield.com. It’s that simple!

Jessica Raymond, Editor editor@maximumyield.com

letters to the editor Order Disorder

Online Education I have recently gotten into the habit of visiting your website and checking out the online tips included with the articles each month. I find them to be very practical and useful.

My favourites this month were the history of organics and information on Dr. Maynard Murray’s research.

I’m certainly not opposed to learning from those that have come before me and adapting their ideas for use with my own devices. Awesome stuff.

Thanks Addison Pierce

I love the rag my friends. Great, detailed information. I especially liked your latest feature by Luis Bartolo, “Our Organic Future.” It is the only way to go. I also hope to see more genetic diversity in production crops.

I’m surprised you guys don’t offer an online subscription form. I usually read the mag online to save paper; however, my Internet connection is buggy at best. I don’t have a printer and I’m not able to print and mail the subscription form. That’s why I’m emailing you guys. Hopefully you can get me set up for a subscription.

Thank you so much Dennis Fernandez

Sustainable Hydroponics I doubt many disagree with the environmental benefits of converting to organics in their approach to growing and living. But how do we merge these two very different growing styles? Advancements are being made in the study of “organiponics” with experimental projects producing real results across the globe. It’s inspiring, and although I’m no scientist, I am a grower, and I say it can be done.

Wendy Lee

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MAXIMUM YIELD UK - July / August 2010

We appreciate your suggestions, and are always working to make our website as practical and user-friendly as possible. If you are unable to print and mail the PDF subscription form found on maximumyield.com, the best method for you to order a subscription at this time is to call our office (1-250-729-2677).

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 editor@maximumyield.com

ASK

erik

My hydroponic tomato plants are up over 1.5 metres tall. How can I stop them from going higher? The norm is 1.2 metres outdoors and I can’t move the light up any higher as the plants are not on the floor.

Roy Thornton

The final vertical height of your crop will have a lot to do with genetics (genotype) of the crop. Some varieties are better suited to growing indoors under lights than others. As you have stated, using the same genetics indoors the plants have become taller versus the same variety you grew outdoors. What you are witnessing is the plants genetic make-up (genotype) being influenced by the physical environment to create a different physical expression of the same genes. This is often referred to as the phenotype; the physical expression of the genes as dictated by environment. Tomatoes are often classified as “determinate” or “indeterminate” varieties. Determinate means they will get to a certain height and mature, while “indeterminate” varieties will continue to grow upwards until they run out of room or as long as the climate allows for.

Indoors, plants may not have to work as hard in some areas, like water and nutrient absorption, while they may have to worker harder in others, such as capturing solar energy from the lighting levels provided by artificial light sources. With this increased level of water and nutrient availability, but less “sun,” the plants are searching for light, fuelled by abundant nutrients; ultimately creating more of a “stretch” in their growth pattern.

If you are running out of room before the plants hit the lights, you can bend, train and even prune the branches and vines back. A trellis support system or 15 square centimetre grid screens can be suspended and secured at the top of the crop canopy.You may have some luck training the branches and vines to grow along more horizontally rather than vertically in the trellis netting, reducing the overall height of the crop. Once the grid is filled, and fruits or flowers have formed, you may choose to remove the main growing point of the tomato plants, so they can concentrate their energy into the fruits and flowers rather than growth.

Most growers find that having more and stronger sources of “blue” light in their artificial light sources helps to keep internodal distances tighter. Lower humidity levels (40 to 50 per cent relative humidity) and more even light to dark cycle temperatures will also promote closer, squatter growth habits in your crop.

An abundance of nitrogen or not in the correct ratio with potassium will encourage more elongated and softer growth in plants, often making them more susceptible to insects and diseases.

Plants produce naturally occurring growth hormones called “cytokinins” that help make them stockier and bushier. There are also naturally occurring soil bacteria that help to release these hormones to plants. Some great 100 per cent organic bloom stimulants are available that will help to supplement these levels, resulting in tighter and bushier plants for growing under lights.You can also inoculate the growing medium and root system with bacterial inoculants designed for use with hydroponics gardens.

Good luck and good growing to you.

Cheers, Erik Biksa 8

MAXIMUM YIELD UK - July / August 2010

MY

MAX

facts

hydroponic news, tips and trivia from around the world

Expansion Plans for Britain's Largest Tomato-Growing Glasshouse _____________________ While this season’s tomato crops have been significantly delayed due to dull weather, a 10-year-old nursery in Wissington, near King’s Lynn, is making plans to expand the largest tomato-growing glasshouse in the country by 7.5 hectares.

The glasshouse containing the tomatoes gets free heat and carbon dioxide from the plant, which doubles the tomato plants' yield, making it an unrivalled and possibly even carbon-negative growing process, a claim that is being tested by Bangor University and the Horticultural Development Company.

In the UK, 80 per cent of tomatoes are imported and 20 per cent are British-grown, proving there is much room for British tomatoes. This year looks set to be a positive one for tomatoes. With imports particularly poor due to bad weather in the Canaries and Morocco, British growers have everything to play for.

(Source: www.hortweek.com)

Asexual Plant Reproduction May Seed New Approach for Agriculture

Sales of Organic Fresh Food Falling in the UK _______________________

Farmers throughout the world spend an estimated £24 billion a year to buy seeds for crops, especially those with sought after traits such as hardiness and pest-resistance.

They can’t grow these seeds themselves because the very act of sexual reproduction erases many of those carefully selected traits.

Scientists are close to turning sexually-reproducing plants into asexual reproducers. The findings raise the possibility that many plants have the ability to reproduce through apomixis, a specific type of asexual reproduction, but that potential is suppressed by Argonaute 9, a large family of proteins that has gained widespread attention among researchers because they control which gene products a cell makes.

Scientists are still working toward creating a fully asexual Arabidopsis plant. Current mutants do not develop completely asexual seeds. But by highlighting the role of Argonaute 9 in plant reproduction increases the slew of agricultural possibilities.

Sales of organic fruits and vegetables are plummeting in the UK according to a report from the Soil Association.

In the past year they have fallen by 12.9 per cent in all as cost-conscious shoppers watched their pennies. The independent sector has been hardest hit with farm shops and health food outlets’ sales dropping by 17.7 per cent. The supermarkets experienced a decline of 12.2 per cent. Sales of boxed fruit and vegetables delivered to the home fell by 9.8 per cent.

The Organic Market Report 2010 is a gold-mine of information on organic food buying habits. It includes details on the average consumer; what they are buying; and what the future holds.

The Soil Association predicts that the organic market will return to growth this year, expanding by two to five per cent. The supermarkets report that sales of organic vegetables are increasing again after more than a year of decline and they account for 73 per cent of the organic market. A survey of 28 leading organic businesses in the UK shows that 61 per cent expect growth and only seven per cent anticipate a further decline in their sales this year.

(Source: www.sciencedaily.com)

(Source: www.treehugger.com)

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MAXIMUM YIELD UK - July / August 2010

Some Britons Not so Hyped About England’s Colossal Hydroponic Complex Thanet Earth Hydroponic farming is coming to the U.K. this summer—70 soccer fields worth of it. The construction of Thanet Earth—a set of seven hydroponic glasshouses—is near completion. The £80 million project will produce 2.5 million tomatoes every week.

But not everyone is thrilled about the project. Growing hydroponic crops year-round could be an energy glutton. You have to shine artificial light on tomatoes to trick them into growing, and 220 acres is a lot of artificial light. Growing hydroponic plants should save water compared to soil farming, but there’s also a lot of good soil now buried beneath glass and concrete, and any archaeologists who many have wanted to excavate the historical area are out of luck.

(Source: http://blogs.discovermagazine.com)

Sustainability Ratings for Restaurants _____ The newly formed Sustainable Restaurant Association will rate restaurants according to how sustainable they are.

The awards are a bronze, silver or gold status and will be listed in restaurant guides. And they will be judged on very rigorous standards.

The Sustainable Restaurant Association is introducing a new rating system based on principles such as buying locally, changing menus seasonally and building relationships with farm producers and suppliers.

Restaurants must pledge to be more sustainable, commit to the values of the organization and carry out at least three new sustainable activities. These cover several different areas: Sourcing (sourcing of food); society (treatment of staff and relationship to the community); and Environment (waste management, energy efficiency and waste saving).

(Source: www.treehugger.com)

MAXIMUM YIELD UK - July / August 2010

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MAX

facts

hydroponic news, tips and trivia from around the world

Manga Micro-Farm Makes for Great Geeky Gardening What can you do with a stack of manga or comics that is destined for the recycling bin? Use them as a gardening medium, of course! At least, that’s what one artist has done in an installation at the Matsuzakaya department store in Nagoya, Japan. By piling up a stack, rubber banding them together, soaking it and sprinkling it with seeds, the artist explores a colourful and decorative way to raise a salad.

PinkTentacle.com shows us the work of Tokyo-based artist Koshi Kawachi, who demoed “Manga Farming.” It’s simply the use of old manga as a growing medium for veggies.

Within the comics, a crop of radish sprouts grow as happily as anything you’d see atop a Chia pet.

While this is an art display, it does make you wonder what you might be able to do with the stack of comics under your bed, or the phone books you haven’t cracked open in the last five years.

(Source: www.treehugger.com)

Longer-Lasting Flowers: Fresh Ideas from Researchers ____________ Tomorrow’s fragrant bouquets and colourful potted plants might last longer, thanks to floriculture research that may help boost their vase life.

In ongoing studies, researchers have shown that spraying low concentrations of a compound known as thidiazuron (TDZ) has significant, sometimes spectacular effects in extending the life of potted plants’ leaves and flowers. In tests with greenhouse-grown Cyclamen plants, TDZ-treated plants had a significantly longer life than did unsprayed plants.

Preliminary studies with cut flowers were the first to demonstrate the value of TDZ for a commercial floricultural species. The Cyclamen experiments are the first to show the leaf-saving and blossom-boosting effects of TDZ with potted floricultural plants.

Though commercial use of TDZ on cut flowers and potted plants seems promising, the researchers’ deeper interest lies in determining precisely how TDZ affects genes and proteins inside the plants.

(Source: www.ars.usda.gov)

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MAXIMUM YIELD UK - July / August 2010

Tomatoes are Top of the Plots ___________ Tomatoes, lettuces and potatoes are the top three food crops in Britain’s gardens and allotments this year as a third of the population grows at home.

Strawberries also remain one of the top favourites. Research places carrots in fifth place with one in five growers opting for them, and herbs—basil, chives and parsley—take the next three places. Beans are in ninth place and onions are at number 10.

A leading seed company claims gardeners prefer traditional root crops to trendier vegetables such as summer squash, Oriental greens and chilli peppers. While British gardeners still love growing and eating their root crops, they now prefer improved hybrid versions of old favourites.

The best seller is the Winter Stews Collection with presown tapes of parsnip, carrot, swede and celeriac. Even turnips and swedes are popular with gardeners.

(Source: www.liveforgardening.com)

St. John’s Wort Collection Mined for its Medicinal Value _____________________ A unique collection of St. John’s wort (Hypericum) is providing university collaborators with genetically diverse, well-documented sources of this herb to use in studies examining its medicinal potential. Scientists are screening 180 properties of St. John’s wort for biologically active compounds and their potential to combat viral infections, reduce inflammation or improve digestive health.

The hypericum collection at the Agricultural Research Service Ames crop genebank was started in the 1990s and today encompasses about 60 species collected from around the world. This diversity has enabled investigations of genetic, environmental and developmental factors affecting the quantity and quality of bioactive compounds, as well as their modes of action.

Of particular interest is how these compounds interact, and whether those interactions are critical to human health benefits.

Recently researchers noted that combinations of four compounds from St. John’s wort were more effective at reducing inflammation in mouse macrophage assays than when each was used alone.

(Source: www.sciencedaily.com)

MY MAXIMUM YIELD UK - July / August 2010

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PRODUCT spotlight

See it. Want it.

Find it at your local indoor gardening store.

Ancient Forest from General Organics Now Available ____________________ General Organics Ancient Forest is a natural soil amendment consisting of 100 per cent pure forest humus. Derived from thousands of years of naturally decomposed forest litter, it contains a wide spectrum of organic compounds. Its high diversity of micro-organisms, including more than 35,000 species of bacteria and over 5,000 species of fungi, make Ancient Forest an ideal amendment for gardening and potting soils. This amendment also aids in the retention of water and nutrients, creating stable, long lasting soil for your garden. Ancient Forest’s immense biological activity also makes it the ideal inoculum for actively aerated compost teas. Ask for it now at an indoor gardening shop.

CANNA® PK 13-14® is Holland’s Secret Weapon ____________________ CANNA® PK 13-14® is the number one bloom stimulant scientifically developed to increase the size and weight of fruiting and flowering plants. Holland’s secret weapon is now available to be unleashed in your garden. This premium Dutch fruiting and flowering stimulant is the industry leader and sets the benchmark for this popular type of additive. Testimonials from countless growers around the globe who use CANNA® PK 13-14® report larger, heavier yields of fruits and flowers with an average yield increase of 35 per cent compared to fertilizer alone. The powerful formulation awards unparalleled flower size, weight and fruit swelling. For more information on CANNA® PK 13-14® from Holland visit your favourite indoor gardening store.

Nutrifield® pH Up and Down ­­___________________________________ pH Up and pH Down are tank controllers that will adjust your solution to the desired pH (the measure of the acidity or alkalinity of a solution). The pH scale ranges from 1.0 to 14.0. pH 7.0 is considered neutral and is based on pure water. Solutions with a pH less than 7.0 are considered acidic, while those above 7.0 are considered basic (alkaline). pH affects nutrient uptake for most plants. The optimum pH range for plants is from 5.8 to 6.5. pH Up and Down comes in both concentrated and ready to use (RTU) forms. Available in concentrated sizes: 240 grams, one litre and four litres. Available in ready-to-use: 480 grams, one litre and four litres. For more information about pH Up and Down please visit your nearest hydro store.

Multi Total Soil Improver New from DutchPro _____________________ This soil improver has been developed to turn dead plant matter into beneficial nutrients.

Multi Total stimulates root growth by the improving soil structure and stimulates the nutrient producing bacterial life in the substrate. It optimizes the water retaining properties of the soil, regardless of soil type. It stimulates the cationic exchange of minerals and micronutrients and improves resistance against fungi and stress situations. Multi Total is a natural, pure and organic product. Suited for every irrigation system and culture on soil, hydro and coco.

Available in 250 millilitres, one litre, five litres, 10 litres and 20 litres. Ask for Multi Total today at your favourite hydro retail store.

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MAXIMUM YIELD UK - July / August 2010

The New Ultrametre II by Myron L Company ______ The Ultrametre II still delivers the most accurate dissolved solids measurements of any instrumentation and the greatest degree of accuracy available for pH, ORP and temperature measurements, but has been redesigned to include an LSI/ hardness calculator, free chlorine measurements and Bluetooth® data transfer.

The hardness calculator is an analyzer that generates a Langelier Saturation Index value useful in determining how to modify hardness, pH or alkalinity to achieve balanced water. The user can accept inferred LSI calculations or input known values for pH, hardness or alkalinity to allow the calculator to determine the LSI value precisely. The user can also select from grains and ppm hardness units within the calculator.

ORP readings can be displayed as mV or ppm free chlorine. This new feature allows the Ultrametre II to measure a dynamic range of sanitizer concentrations wider than that of a colorimetric test kit.

For more information, please contact your local indoor gardening product retailer.

Announcing Atami Wilma 9 ______________ Riding on the incredible success of the Wilma Grow System, we are pleased to announce the arrival of the Wilma 9.

Features: • bigger plant spacing allows you to grow big • 18 litre pots for increased root mass • 1.2 metre system fits the Wilma tent perfectly Why use a Wilma?

• effortless set-up and automatic feeding saves hours of work • excellent drainage no matter which medium is used • easy pump access for maintenance and monitoring • of nutrient solution • high quality pots are the ideal size and reusable • self-contained system greatly reduces chance of leakage • comes with a selection of drippers suitable for any medium Success guaranteed!

Visit your local hydro retailer to learn more.

MAXIMUM YIELD UK - July / August 2010

15

PRODUCT spotlight

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

Plagron Introduces Green Sensation with an Improved Formula Plagron is excited to introduce worldwide the second generation of Green Sensation. The new Green Sensation has an improved formula, which results in higher yields and also a higher nutrition value, saving more of your basic nutrients.

Because Green Sensation is less thick, it mixes more easily with water making it easier to use. The method of use is the same and you can even mix the old and new Green Sensation.

The new Green Sensation can be used on all substrates (soil, coco, rockwool, mapito, Eurofoam, etc.) and with all kinds of watering systems (NFT, tide systems, drippers, etc.).

Throughout its long history, Plagron has specialized in the development of products for optimum natural growth and blooming. We carry a wide range of environmentally-friendly additives that are the world’s best. For more information contact your local hydro shop.

CANNA® Terra® - Holland’s #1 Home Grow System ____________ Growing using the Terra® system from CANNA® is very productive and profitable.

CANNA® Terra® is Holland’s #1 grow system for home growers. Log on now to www.canna.com.au/my for your free 28 page report in which we tell you about some of the major errors hydroponic growers make and how to avoid them. We will start by looking at how peat—the major ingredient of CANNA® Terra® Professional—is made, the structure and the different types of peat. On top of this we will give you some valuable tips to irrigate correctly, start seedlings and increase your yield using CANNA® Terra®. For more information on the CANNA® Terra range of gardening products from Holland visit your favourite hydroponics retailer.

Nutrifield® Herbal Boost ______ Plant Magic Plus Soil Supreme ___________ Herbal Boost is an organic growth stimulant that boosts your plant’s immune system against insect infestation.

It is sourced from the roots of an ancient Chinese tree root called Sophora. It has long been used in Chinese natural medicine and is a product of many years of research in Chinese medicine and its applications in today’s society.

Detailed research has shown that the product works by stimulating a plant’s phytoalexin production. Phytoalexins are antibiotics that are produced by plants that are under attack. When produced they act as toxins towards the attacking organism. Not only will Herbal Boost strengthen your plant’s immune system, it will invigorate your plants by producing strong healthy roots and green lush foliage.

Herbal Boost will become inactive when used with products with high alkalinity. For more information about Herbal Boost, please visit a hydro shop near you.

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MAXIMUM YIELD UK - July / August 2010

Soil Supreme is a unique blend of sphagnum peat, fytocell foam and our very own organic growth stimulant.

This combination will ensure that your plants experience a superior root environment. This leads to rapid root development allowing for a more rapid uptake of vital nutrients and elements. The results are impressive, with bigger, better tasting fruits, increased yields and flowers with enhanced colour and aroma.

Fytocell foam is 100 per cent biodegradable and harmless to the environment. It is also excellent at retaining moisture with a great aeration rate.

Our organic growth stimulant will see that your crop benefits from improved quality, flavours and aromas and an increase in yield. Our organic growth stimulant is also a great food source for beneficial fungi and microorganisms. Available in 50 litre bags. Visit your favourite hydro retailer to learn more.

Leaf Green for Good Leaf Development New from DutchPro ________________________ Leaf Green gives your plants health and vitality. Leaf Green is especially recommended for plants that have noticeable difficulties with their development. It also gives yellowing plants a fresh green colour. Leaf Green is good for leaf development, improves leaf colour and improves nutrient uptake. Spraying on the leaves should be done at least three hours before the lights go on. Available in one litre, five litres, 10 litres and 20 litres.

New Safer® Brand Insect Killers at BWGS ____ Safer® Brand End All Insect Killer is ready-to-use and kills 45 different insect species in any stage of life, from egg to adult. It’s effective against aphids, various beetles (including Japanese beetles), caterpillars and larvae (including gypsy moth caterpillars and tent caterpillars), harlequin bugs, leafhoppers, mealybugs, stink bugs and whiteflies. OMRI®-listed Safer® Brand End All can be used up to the day of harvest on ornamentals, trees, shrubs, fruits, vegetables, flowers and houseplants and is compliant for use in organic gardening.

OMRI Listed® and compliant for use in organic gardening, Safer® Brand Garden Dust effectively kills caterpillars, corn earworm, bollworm and more than a dozen other types of worms. Once ingested by the wayward pests, the active ingredient bacillus thuringiensis kills them within a few days.

Ask for it today at your favourite hydro retail store.

Simple and Effective – Nutriculture Gro Tanks _________________ In a Nutriculture NFT Gro Tank the nutrient solution is contained. Your plants sit on a tray above the tank and nutrient solution flows over the roots of your plants. Unused nutrient solution drains back into the tank to be re-used.

Why choose Nutriculture NFT systems?

• faster growth rates and four times the yields achieved with traditional soil methods • no complicated delivery systems, no feeding schedules to calculate, very little maintenance involved • harvest sooner and get more crops per year • no waste runoff in re-circulating hydroponic systems • no chance of over or under watering • clean and minimum waste produce—no heavy bags of medium to carry around • reduced chance of disease and reduced use of pesticides Continued on page 48 For more information visit your favourite hydro retail shop.

MAXIMUM YIELD UK - July / August 2010

17

Growing Up Tower and vertical Systems for small spaces

by Dr. Lynette Morgan Whether you are growing in a commercial greenhouse or an indoor hobby garden, maximizing space is always an objective.

Indoor cropping areas need specialized equipment—fans, vents, heaters, coolers, pumps and lights that will provide for all the plant’s needs in its protected environment, and these can be expensive to set up and run. As growers we take pleasure in our work; giving our plants a comfortable space and providing optimal conditions for growth is highly rewarding. By optimizing the carefully designed growing environment, we are helping eliminate plant stress, and in turn we get a high level of productivity and maximum yields from a relatively small space.

Many new growers make the mistake of cramming as many new plants as possible into a small area not realizing just how quickly they will grow and expand to fill every available space, creating a tangled jungle that becomes a mission to prune, train and control. Small, short plants such as lettuce, strawberries and many herbs never reach an impressive degree of height and may not seem to make the most of limited indoor space. This is where vertical systems really have an advantage.

Vertical, wall or tower/stack systems for hydroponic production are nothing new. In the early days of commercial hydroponics, vertical systems consisting of long, thin tubes of growing media such as sawdust were suspended from overhead rails and planted down each side with small crops such as strawberries. Nutrient was drip fed from the top and drained out the base and many of these ‘tubes’ were in excess of 1.8 metres tall. While the idea of vertical systems obviously appealed to greenhouse growers to increase plant density dramatically, there were initially many problems with the early systems and some complete failures occurred. We have learned a great 18

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Vertical systems can increase the number of plants grown in a small space by a large factor.

“Vertical systems create ‘multiple environments’ within the levels or layers of the growing area.” deal from these initial attempts with vertical growing and modified the concept of stack cropping to the point where highly successful systems have been developed along with the equipment required to run them correctly.

Vital light To the uninitiated, the concept of a vertical system may seem a daunting concept. Most beginners start with traditional horizontal or single plane cropping with all the plants sitting on one level Column systems are best below an overhead suited to climates with high light, as shading on the light source. This lower levels always occurs. makes controlling light relatively simple by adjusting the number of lamps overhead and their distance from the plants. In a greenhouse, growers carry out the same adjustment with the use of supplementary lamps in winter and shade screens, as required, in summer. Each plant has uninterrupted light from above and, in a well run growing area, all plants have the same root conditions and environment.

Vertical systems create ‘multiple

environments’ within the levels or layers of the growing area that need to be carefully managed and planned for. Plants growing at the top of a vertical system receive the highest light (assuming only an overhead light source is available); there is then a gradient of light from the top to the base of the vertical system along with shading from those plants on the upper levels of the stack. In basic systems, or those with no additional side lighting, this shading and light fall-off effect is often what causes problems in naturally lit and growroom-based vertical systems. For this reason, we mostly see successful commercial vertical systems in climates with naturally high light levels that allow acceptable production on the lower, shadier levels of the system.

For indoor growers utilizing artificial light, vertical cropping has much more potential and some excellent systems have been developed, particularly those that incorporate their own light source. Artificial lighting these days doesn’t need to be placed above the crop; side or central vertical lighting can provide sufficient illumination so even the tallest vertical system gets the same intensity of light on all plants in all levels of the stack.

Further more vertical systems that rotate help eliminate problems with shadows and uneven illumination so that lighting is used even more efficiently. Indoor gardens with reflective wall and floor surfaces further assist to bounce light back onto the plants so that a highly efficient system can be maintained year round. In comparison outdoor or greenhouse vertical systems in even high light climates, can suffer from uneven illumination due to shading from other stacks, greenhouse structures and on cloudy days.

Maximum light interception by all plants is an important factor to consider with vertical systems.

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Growing Up: Tower and Vertical Systems for Small Spaces Vertical varieties The vertical systems available to hydroponic growers nowadays are quite impressive. We have come a long way from plastic tubes filled with sawdust suspended from a rail. The design of the vertical is important as it determines the root volume available to each individual plant; how the nutrient is delivered and the flow passage of moisture down the system; the collection system at the base of the stack; and how air may move under and around each plant for humidity control.

System design can also affect light interception by plants and the amount of space each has for upward growth and development. Many vertical systems rely on the use of a high quality growing media to support the plant and provide a reserve of moisture; however, solution culture and aeroponic vertical systems are also available.

Vertical systems come in a number of designs: there are the standard ‘tube’ systems, which are the most basic and consist of a straight column into which plants are spaced at uniform intervals. An advancement on the basic tube, there are also ‘stack’ systems, which involve individual planting units stacked on top of one another, creating planting spaces or pockets for each plant.

There are also vertical systems that don’t rely on circular ‘column’ type structures but consist of tiers of growing Multi level growing trays or beds are commonly found in greenhouse systems and help maximize greenhouse space.

Vertical systems can be either based on substrate or solution culture methods.

channels, beds or chambers that can be constructed from the floor to almost the top of the growing area.Vertical systems may also be complete ‘walls’ of plants, particularly when used for display purposes. Some of the more advanced vertical systems rotate around a light source, while others are so fully automated as to move the plants to a nutrient feeding station at regular intervals.

Making use of vertical space can take on many forms and is suitable for a range of smaller plants.

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Benefits of vertical cropping The benefits of a successful vertical system are fairly obvious; the number of plants that can be grown per unit of floor space is impressive, many times more than can be supported in single plane cropping. Although because of the much higher density, other factors, such as the requirement for more light, side lighting and a greater degree of air movement and ventilation, should be taken into account. In a system where as many as 20 times more small plants can be grown, provided sufficient

Strawberries and lettuce are commonly grown in vertical systems.

light has been provided, the increase in productivity can be impressive and worth the extra degree of skill it takes to manage such intensive cropping. Another benefit of vertical systems that has attracted the attention of indoor landscape artists is the fantastic displays that can be created. A diverse assortment of smaller fruits, vegetables and herbs are suited to vertical cropping, as are many flowering, scented and ornamental plants creating colourful, living floral displays or ‘green walls’ to bring a touch of nature inside. The concept of ‘green walls’ which are simply vertical type NFT systems, is a concept that is catching on worldwide as a way of providing green spaces indoors.

Overall, while vertical systems create more of a challenge than single plane cropping, the maximized use of growing space, potential for much higher yields and impressive display created by a wall of green is well worth the effort.

On maximumyield.com we detail the potential problems associated with growing vertically.

“Vertical systems featuring a diverse assortment of fruits, vegetables and herbs plus flowering, scented and ornamental plants are colourful, living displays that bring a touch of nature inside.”

Free draining media like perlite is well suited to use in tall vertical systems, as it helps prevent oversaturation at the base of the stack.

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Biostimulants

What are they and how do they work?

by Luis Bartolo

To provide answers to these questions we need to go back in time to the 1960s. Dr. T.L. Senn from Clemson University found that high levels of natural plant hormones in seaweed, called cytokine, stimulated plant growth. At that time, stabilizing these Plant Growth Hormones (PGH) was difficult. When they were applied to plants the results were unpredictable and inconsistent.

In the early 1990s agricultural chemists developed techniques to stabilize these plant hormones.

Adding small amounts of PGH with foliar nutrients further improved plant responses compared to applying foliar PGH or foliar nutrients alone.

This led to further investigation into the effects of cytokine, humic acid, salicylic acid and other plant growth hormones to reduce plant stress, including that caused by drought. Cytokine from brown seaweed beds near Norway and Nova Scotia, Canada were found to be highest in cytokine PGH. PGH cytokine works by increasing the in-plant (endogenous) natural production of antioxidants. In plants, antioxidants a-tocopherol (vitamin E) and ascorbic acid (vitamin C) are concentrated in the chloroplast and protect the photosynthetic apparatus when a plant is subjected to stress, by scavenging excessively reactive oxygen species known as free radicals.

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“Of organic substances, marine algae contain, in addition to carbohydrates, proteins, fats, and vitamin substances of a stimulating and antibiotic nature.”

— Dr. T.L. Senn

What are biostimulants?

A biostimulant is as a substance that is neither a plant nutrient nor pesticide, but positively impacts plant health. Consider the definition of a plant growth hormone biostimulant: an organic material that when applied in small quantities enhances plant growth and development so that the response cannot be attributed to the application of traditional plant nutrients.

Biostimulants have been shown to influence several metabolic processes such as respiration, photosynthesis, nucleic acid synthesis and ion uptake.

Biostimulants are not meant to correct a severe nutrient deficiency, but are mixtures of one or more elements—microorganisms, trace elements, enzymes, plant hormones and seaweed extracts. They may enhance nutrient availability, waterholding capacity, increase antioxidants, enhance metabolism and increase chlorophyll production.

Types of Biostimulants Presently, the following main bioactive compounds or classes have been recognized as having biostimulant characteristics: seaweed extracts, plant extracts, amino acids, oligosaccharides, salicylic acid and humates. There are others but they have not proven to be as effective.

Humus and humic acids The term “humus� dates back to the times of the Romans when it was frequently used to designate the soil as a whole. It was later applied to the organic matter portion of soils.

The best source of humic acid is found in layers of sedimentation of soft brown coal called leonardite. This substance is a soft waxy, black or brown, shiny, vitreous mineraloid that is easily soluble in alkaline solutions.

Both fulvic and humic acids have shown to have positive impact on plant growth. They also increase the availability of micronutrients, phosphorus and potassium. Furthermore, they buffer plants from too high concentrations of fertilizers salts. Besides acting like a buffer they increase germination rates and fibrous root growth.

While originally referred to as soil as a whole, humus now identifies the organic matter portion of soil (above). Leonardite, a sedimentary, soft, brown coal, is an ideal source of humic acid (below).

Amino acids Amino acids are building blocks for proteins and enzymes. Some free amino acids, such as proline, improve osmotic adjustment and water-stress tolerance of plants. Amino acids have been shown to stimulate biochemical and enzymatic processes in the plant. Amino acids are also optimal chelating agents for cationic micronutrients.

Bio-Synergy with the power of nature Most organic biostimulants are at their best when combined with fertilizers. Their low nutrient content makes them less effective when used alone, except for in certain situations. Certain plants may naturally respond better than other types of plants. Biostimulants act in synergy with plant nutrients.

There is still a lot of work to do and science organizations and universities are still working hard to uncover more facts about the benefits of organic biostimulants and biofertilizers. The one takeaway is there may be nothing MY more powerful than nature regenerating nature.

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GROWING ROOT VEGETABLES IN

HYDROPONICS Root vegetables are very easy to grow in hydroponics allowing for outstanding quality and excellent flavor and nutrition.

Root vegetables are very easy to grow in hydroponics allowing for outstanding quality and excellent flavor and nutrition.

There has been little research on growing root vegetables hydroponically; however, NASA has been growing sweet potatoes in hydroponics as a possible food crop for space voyages. NASA has even developed a breakfast cereal using this high protein potato, but the gene altering process is highly controversial.

Gericke’s potatoes The first recorded hydroponic root experiments were completed by William Gericke in the early 1930s. Gericke’s first crops were in troughs dug into the ground, filled with a moss like media and a 90 day supply of water below.

Following Gericke’s basic concept, I built a garden of 10 plastic tubs, and put a drain a few centimetres from the bottom.

I used perlite and filled the containers to about 20 centimetres deep.

The very first root vegetables I tried to grow were radishes. The red globe table radish is one of the easiest garden vegetables 24

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to grow, and usually can be grown from seed to radish in a single month.

But the radishes I grew in my normal hydroponic nutrient, a formula rich in nitrogen, did not grow into normal radishes. While the leaves of the radish were huge, very green and lush, the root system was slightly red and thick, with no radish bulb. I tried a few crops and almost all the radishes were too small to be eaten.

The nutrient’s ratio of nitrogen to phosphorus was about 15 to five. The plants continued to put on green growth, and did not build up roots.

I started experimenting with a hydroponic root nutrient, one that has a relatively even amount of nitrogen to phosphorous and even more potassium.

The new nutrients increased the amount of mono potassium phosphate in the nutrient formula.

This restructured nutrient took about a year to perfect, and now wonderful radishes grow as well as other root vegetables. I have tried it with radishes, ginger, potatoes, sweet potatoes, carrots, turnips, onions, garlic and other root

}

by Peggy Bradley

and tuber vegetables. It grows a high quality product with very little effort.

Potato Potatoes should be started by seed.

The red potato and the Yukon gold are two of the best varieties for growing in hydroponics. When planting potatoes in soil you can cut them up into many pieces for planting. But, you must make sure that each piece has at least one eye, which is where the potato starts growing.

However, this can be problematic and it is easier to plant the entire small potato in the media. I use a fluffy perlite media, one that can be dug into under the plant.

The potato should be buried so that the top surface is about 2.5 centimetres below the media.

It should have about two to 2.5 centimetres of media under the plant to give room for the roots to be in moist media. The drain hole or standing water should be about 2.5 centimetres deep at the bottom of the media.

After the potato is first planted it should be watered from above every day, making sure any excess is drained from the container. The roots should start forming from the lower eyes and the shoots or green parts from the upper eyes. Green material should appear at the surface of the media in about a week. If two weeks go by and nothing forms, dig up the potatoes and look at them.

If the potatoes have not formed any roots, rotting instead, the substrate was likely too wet or the seed potatoes might not have been any good.

I grow potato plants in a nitrogen rich grow nutrient until they reach full height, usually from 45 to 60 centimetres tall. A 60 square centimetre tub can have two plants in it. When they are full height, or starting to show the first blossoms, switch the plants to a root nutrient. Then small potatoes should start forming on the roots.

About two weeks after the first potatoes form, one potato should be ready to harvest.

You have to feel around under the plant to find the largest potato. It may be that the potato stores all its energy in one potato, then the next.

According to Gericke’s information, a one pound potato can be harvested from each plant every four days. It you want two pounds of potatoes every day, you need about eight plants. The hydroponic potatoes are free from musty flavour and will probably be the best you have ever eaten.

Carrots Carrots are grown in a softer media such as perlite or sand. Short carrots work best in hydroponics because the media depth has to be about 60 centimetres taller than the length of the carrot.

Carrots cannot be transplanted so they must be planted where they will be grown and harvested. If you try to grow

and then transplant them, the resulting carrots will be twisted and follow the path of the transplanted root.

A two metre deep tub is adequate to grow carrots. The seeds should be planted about 2.5 centimetres apart so 30 square centimetres can grow 144 carrots. They should start producing carrots in about 90 days.

If you want a supply of carrots every day you should have about 1.8 to 2.5 square centimetres of carrots in production.

Ginger A ginger plant looks like a delicate and graceful bamboo.

The root that grows below yields a bit of fresh ginger every day. A single plant will g r o w to about 60 to 90 centimetres high and about that in width. A 60 centimetre tub will house only one ginger plant and will produce only about 60 to 90 centimetres of fresh ginger root every day. This is not a productive plant, but the

fresh ginger is a wonderful addition to a daily diet, and has important medicinal properties.

Sweet potatoes Sweet potatoes are started from small plants placed in a bed of sand, and supplied a small amount of moisture. The springs should appear within a week of two of planting.

Sweet potatoes from the store may not sprout at all as they may have been treated to prevent sprouting. Sweet potato seeds from nurseries and organic sweet potatoes from farmer’s markets may sprout. The sweet potato is grown like the potato, but is slower to form. Sweet potatoes are more nutritious than the white potato and have a high vitamin C and vitamin A content.

Hydroponics offers an excellent alternative for growing root crops, eliminating soil-borne pests and producing huge yields of nutrient-rich, flavourful, quality crops.

References Hagan, H. 1995, Fertigation: An overview of some practical aspects Introduction http://iclfertilizers.com/pdf/1-1.pdf Hill et al. Utilization of sweet potatoes in controlled ecological life support systems (CELSS). G.W. Carver Agricultural Experiment Station, Tuskegee University, AL 36088, USA. Imas, P., Recent Techniques in Fertigation of Horticultural Crops in Israel c/o Dead Sea Works Ltd., POB 75 Beer Sheva 84100 Israel. http://www.ipipotash.org/presentn/rtifohc.html Kafkafi, U. SEVEN LECTURES ON SELECTED TOPICS, Sponsored by Haifa Chemicals Ltd http://departments.agri.huji.ac.il/plantscience/topics_irrigation/uzifert/2ndmeet.htm Mantag, Uzi, 1999, Fertigation in Isreal, www.fertilizer.org/ifa/publicat/PDF/1999_biblio_20.pdf Waisel Y., A. Eshel and U. Kafkafi (eds.). 2002. PLANT ROOTS. THE HIDDEN HALF. Marcel Dekker, Inc. New York, Basel, 3rd. edition.

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by Erik Biksa

next generation LEDs

Enter the Quad Band The last time we discussed LED (light emitting diode) technology for plant growth, we looked at dual band (red/ blue) light spectrums in the 0.5 to one watt diode range.

The overall output of the panels ranged from 45 to 90 watts.

LED technology for plant growth is being developed at an accelerated rate, and studies show LEDs are a viable technology for providing artificial light energy to fuel the photosynthetic response. However, first generation LEDs had some limitations; the dual band spectrum provided only red and blue light wavelengths. While these bands are where most of the photosynthetic response occurs, additional activity occurs in other spectrums of the visible light bandwidth.

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Imagine this: blue and red wavelengths of light are like macronutrients, while other bandwidths are more like micronutrients. Micronutrients are just as important as macronutrients, the difference being they are used in much smaller quantities. It’s about supplying the correct and exact ratios of each. HPS and MH lighting produce huge quantities of spectra output that the plant uses very little of, making them less efficient although effective because they are full spectrum.

Furthermore, the exact spectral output of the diodes—measured in nanometres (nm)—has been fine tuned in next generation LED lighting so that the output occurs where the most light energy intensive reactions occur. In order to provide a complete,

“Plants will naturally grow shorter and tighter under blue light so growers can sacrifice some intensity for more light coverage per LED fixture.” although not very intense full spectrum light source, with earlier, first generation LED grow lights, the LEDs were supplemented with full spectrum CFL or T5 fluorescents to meet the needs of photosynthesis on all the necessary wavelengths.

The result using first generation LED lighting was a source of light for plant growth that used minimal electricity and delivered the required wavelengths of light to sustain healthy plant growth. Different types of plants also seemed to require different wavelengths of light at different times. The earlier LEDs were capable of producing healthy growth for rooting cuttings, young plants, seedlings and vegetative growth. The growth was exceptionally healthy and “hard” and supported relatively rapid development.

The first generation LED units contributed to an exceptionally cool growing environment, which allowed for the use of supplemental CO2 enrichment to be applied very easily and cost effectively, further accelerating growth rates, plant health and yield potential. In our early test model, we were able to maintain CO2 levels of between 1,200 and 2,800 ppm in the

Next Generation LEDs growing environment by the use of fermentation in a sealed grow tent.

Noticeably faster growth rates occurred, and the by-product of the fermentation, beer, was an added bonus. Not only did this set-up require less energy, it was economical, an important consideration for urban growers.

The earlier LEDs delivered good results relative to the amount of electricity they consumed, although HPS and MH High Intensity Discharge (HID) lamps seemed to win in terms of yield in the bloom phase, although with a lot more noise, heat and at least triple the electrical consumption when factoring all of the peripheral equipment required to manage the heat levels.

To be fair, if the earlier dual band lower wattage systems went watt-to-watt with HIDs, they were capable of surpassing yields

“Powerful deep red wavelengths supplied by far-red LED diodes stimulate lots of flower and fruit development.” and crop quality in many types of plants. One drawback was that certain types of plants that had a definite “finish” in their lifecycle sometimes took prolonged periods of time to ripen; this was attributed to limitations created by the dual band spectrum, although supplemental full spectrum fluorescent light alongside the LED panels helped improve this issue.

Due to their relatively lower intensity, and therefore limited ability to deliver high levels of light energy, it was recommended that those interested in LEDs select auto-flowering plant varieties that mature under longer photoperiods and finish

Given how little of the LED’s output is in bandwidths that are measured in lumens, this reading suggests that this LED lighting system is incredibly intense (+7000 lumens).

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Sweet and innocent looking It’s hard to believe but this simple looking LED crop light fixture keeps up with 1,000 watt HPS lighting, using about a third of the power.

relatively shorter in stature, for example, less than 45 centimetres tall. This way, the plants were able to receive significant light levels from top to bottom, with more consistent quality in all harvested fruits and flowers.

So here we are today, with the next generation of LED crop lights available. The future is looking very bright and cool indeed. New developments and refinements from leading LED manufacturers include grow lights that use one-third of the power on lighting alone, run very cool relative to their light output and are capable of competing with 1K (1,000 watt) HPS lamps in terms of growth rates, yields and cropping time.

The unit featured here produces light in the following ranges: 455-475 nm (blue), 620-630 nm (red), 660 nm (far red) and bright white (full spectrum, 2700K); hence it is a quad-band LED crop light.

Quad band LED spectral output (327 Watts) When compared against the known photosynthetic response curve, quad band LEDs maximize the areas of highest photosynthetic activity in their output.

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Next Generation LEDs Broadside LED lighting: LEDs work great at any angle, so they can broadside larger plants with intense light or provide side lighting in HID lit gardens.

There was never any question as to whether LEDs were effective for vegetative growth. It now appears that LEDs are ready to give crops everything they need for high yields and vigorous production in bloom: intense light levels in balanced spectral ratios and excessive heat eliminated. All of this with about half the power consumption in lighting alone, and significantly reduced costs in cooling equipment required and the relatively high level of electricity required operating energy intensive appliances such as ACs, chillers and industrial fans.

These units contain more diodes compared to first generation LEDs with higher wattages. The diodes are approximately two watts each, although the power they are driven to is dependent on the individual spectral outputs engineered into each of the different LED chips on the lighting board.

Some practical ways to increase the plant’s metabolic rates and transpiration of water through the leaves (for both grow and bloom phases):

Increased air circulation (be careful not to keep fans too close to plants) Slightly lowered humidity levels (for example 40-50% RH versus 50-65%) Applications of bio-stimulant plant additives that enhance the plants metabolic rate of activity. These formulations often include full spectrum B-vitamins, co-factors, humates, fulvates and L-amino acids Additions of fulvic acid with base nutrients Faster draining growing mediums; for example with additions of perlite or drainage layers

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1A-HPS VS quad band for photosynthesis Looking at this chart, we can see that quad band LEDs appear to be better tailored to the known photosynthetic response curve VS HPS lighting.

These cutting edge LED chips are driven at much higher frequencies. The difference is significant; now the chips can be driven at hundreds of milliamps instead of tens of milliamps.

This fuels the process at which electrical current is passed through the chip and energy, called electro luminescence, is released. In laymen’s terms: bigger LED chip + more milliamps = very bright light. While more milliamps are being passed through the individual LED chips, the overall amount of power consumed is still relatively low to the intensity of the light produced, making the next generation of LED crop lighting technologies extremely efficient.

Now with all of this output, surely there must be a lot more heat? The answer is no. Even at more than 10X the

Looks can be deceiving When not powered, the individual diodes appear rather tame; however, when powered on, they are blinding.

light energy output versus the earlier 45 watt dual band, smaller wattage diode panels, these higher wattage LED systems run incredibly cool relative to their light output; retaining all of the benefits from the first generation of LEDs while delivering a broader and more intense source of light for bigger yields and faster finishes.

It is true that you can expect to pay near three times more for a high-output quad band LED system over a standard or a cost effective digital 1,000 watt HPS/MH ballast, bulb, high quality reflector and cords. While that might stop some people in their tracks, take the time to consider the following.

The 1,000 watt HPS will draw about three times more power to produce the same light intensities in the bloom 610 to 680 nm range. In fact, the LED will produce a higher quality of “red” light in the bloom phase because the diodes/chips allow for light wavelengths to be tailored very exactingly. Little can be done to enhance the spectrum of HPS lamps, although the horticultural HPS lamps are superior to standard lamps. Now if you live somewhere where electricity is expensive, or want to run multiple lamps, the savings actually pays for the difference within a short time frame. For example:

HPS lamp spectral output (1000 watts) HPS lamps produce a lot of yellow and orange in their spectrum, falling short in the red and far red wavelengths relative to the overall output.

All lit up Here we can see that different diodes are giving off different light wavelengths; they are installed in exacting patterns and ratios for optimal plant lighting.

Consider that every six months to maintain optimal light levels, the HID bulbs will require replacement. With LEDs they will require no replacement for over 50,000 to 100,000 hours. To save you from doing the math that means they will run for at least 10 years before needing replacement using a 12 hour lighting cycle.

In my opinion, it will take some time before growers are able to confirm these findings. However, it is clear that tremendous cost savings are offered in terms of lamp replacements and more importantly the cost of electricity.

When considering an LED lighting system to replace your HID lamps, be advised that not all LED crop lighting systems perform the same. In fact, there are worlds of difference between the LED lighting systems produced by different manufacturers.

With HID and fluorescent lighting technologies, there is a level of standardization due to the widespread use and manufacture of the technology.

With LEDs, the possibilities when factoring in the various

“With high-output quad band LEDs available, a growing renaissance is not far off.” wattages, quantities, types and ratios of diodes/chips coupled with the different drivers to light them make the different possibilities with LED lighting systems virtually limitless. This means that the prospective LED growers need to choose their LED lighting system carefully to avoid disappointments. With a lot of LED technologies, the old adage, “you get what you pay for,” certainly rings true, although you can’t choose on higher prices alone to discern which one is going to work best for you.

Also remember that comparing LEDs with lumens is almost futile, because lumens are typically measured in the 555 nm range (yellow/green light), something that LED lighting systems are specifically engineered to have lower outputs of to increase their efficiency. Plants only use yellow/green light in very small quantities while the majority of the photosynthetic activity is on the blue and red ends of the spectrum. Do some research, check out what kinds of reviews everyday growers are giving the LED system you have in mind. In doing so keep in mind, that LEDs vary greatly from manufacturer to manufacturer and someone who simply states that LEDs in general terms are either “good” or “bad” hasn’t really told you anything at all. Which LED MY system they are referring to is most important.

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by Philip McIntosh

The Tiny and the Powerful

Viruses in Hydroponic Plants 34

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People are generally afraid of viruses. This is understandable.

After all, they are quasi-living particles that invade cells to hijack their molecular machinery, forcing the cells to make more viruses. They are too small to be seen with all but the most powerful microscopes. Some can be crystallized and stored in a jar on a shelf for years without losing their potency. Sometimes they even insert themselves into the DNA of their victims and ride around for awhile before popping back out to do their mischief. There’s no two ways about it: viruses are strange, fascinating and sometimes even dangerous.

Viruses cause many of the familiar and terrifying maladies that have plagued our species since before recorded history. Measles, mumps, small pox, chicken pox, polio, yellow fever, influenza and AIDS are all viral diseases. It was not until the advent of vaccines beginning with Edward Jenner’s successful inoculations against small pox in the 1790s that we had a way to combat these mysterious infectious agents.

Perhaps less in the public eye, are the many viruses that infect plants to cause their own sort of mayhem in the realm of human agriculture. We owe the very discovery of viruses to the investigation of a once highly destructive disease of plants— tobacco mosaic disease.

A Bit of Virology

designed to read RNA molecules to build plant proteins get to work making viral proteins, including more copies of the viral replicase, and more copies of the original viral RNA. When all is said and done, the freshly synthesized viral proteins reassemble into capsids, which encapsulate the newly made copies of the viral genome along with a bit of viral replicase. These new viruses are ready to spread through the plant or be transmitted to new host plants.

In 1892 Russian scientist Dmitri Iwanowski discovered the first virus. He was looking for the cause of the mosaic disease of tobacco, suspecting that some sort of microbe was involved. To his surprise, whatever the infectious agent Viral Plant Diseases Edward Jenner was, it was too small to be In general, viruses are usually quite host-specific. They aren’t filtered out of a liquid infusion made from diseased leaves. known to cross kingdom lines. In other words, we humans His ceramic filters had pores small enough to trap all known have nothing to fear from plant viruses. Moreover, viruses are bacteria. The culprit was very small. Some people reserve the somewhat particular about which plants they infect. Plant credit for launching the science of virology viruses usually infect a narrow range of host for later workers since he really didn’t know plants, but some can infect a range of species. what he had, but he did realize it was unlike Plant viruses are seldom lethal to their any previously known infectious agent. hosts, but that doesn’t mean they can’t be a Research on these un-filterable germs big problem. Productivity can be seriously continued for decades, and they became reduced and the unsightly appearance of the suspected causative agents for more and infected plants makes them unmarketable. In more diseases of both plants and humans. nature, plant viruses are rarely devastating, but It took a Nobel Prize-winning invention in a monoculture (which is usually the case in to finally reveal the true size and hydroponics) they can be quite destructive. appearance of a virus. In the 1930s, the newly developed electron microscope was Viral Diseases of Lettuce used to obtain the first fuzzy images of Probably the most common viral disease the thin rods characteristic of the tobacco of lettuce is big vein disease, which is mosaic virus (TMV). occasionally seen in hydroponic plants. As the Viruses truly are weird. They don’t fit name suggests, infected plants have unusually into the normal scheme of living things. prominent leaf veins. The veins don’t However, they posses what is perhaps the actually get bigger; they just look bigger most important characteristic of life—the because of a loss of chlorophyll in the region ability to reproduce to pass genetic surrounding the veins. Infected plants have information forward through time.

Figure 1. Diagram of TMV showing visibly yellow venation and shrunken leaves. the spirally built protein coat (capsid) Viruses are built upon variations of a simple The disease has been recognized from the 1930s surrounding the RNA genome. design and they don’t have much in common but only more recently have viruses been clearly with cellular life forms. Taking TMV as our model once implicated. One or perhaps two viruses are the culprits, but again, a plant virus consists of a protein coat called a capsid, they need some help. The soil-borne fungus olpidium brassicae which encloses a single strand of ribonucleic acid (RNA) is a required vector (the fungus transmits the virus to plants). (figure one). Cellular life forms have double-stranded Outbreaks are favored in cooler temperatures (below 20°C). deoxyribonucleic acid (DNA) as a genetic material but Keeping out contaminated soils, as might viruses can have single or double stranded DNA or RNA as be tracked in on the bottom of shoes, is the a genetic material. main means of preventing introduction of Viruses are transmitted to plants by insects by being blown the fungus and virus. Some lettuce cultivars though the air; by exposure to contaminated water, soil, tools, are resistant to big vein disease. people or other materials; or by plant-to-plant transmission Lettuce mosaic disease is another widely from parent to offspring. When a virus penetrates the host distributed viral disease. It is transmitted by plant, it must find its way into a cell. Once inside a cell, the aphids, infected pollen or by infected seeds. capsid disassembles to free the RNA inside. RNA viruses also Ensuring the quality of your seed source and carry with them a protein called a replicase that immediately controlling insects in the environment are the gets to work making copies of the viral RNA that can be best ways to prevent it. Symptoms include used as messenger RNA by the plant cell. Unfortunately chlorosis (loss of chlorophyll to produce a for the host plant, it can’t tell that this viral RNA is not splotchy yellow appearance), tissue death and its own, so the molecular systems in the plant cell that are vein yellowing.

MAXIMUM YIELD UK - July / August 2010

35

Viruses in Hydroponic Plant

PLANT

DISEASE-CAUSING VIRUS

Tomato

Cucumber Mosaic Tomato Bushy Stunt Tomato Mosaic

Tomato Ringspot Tomato Spotted Wilt Tomato Mottle

Lettuce

Alfalfa Mosaic Big Vein Cucumber Mosaic

Tomato Spotted Wilt Turnip Mosaic

Cucumber

Alfalfa Mosaic Beet Curly Top Cucumber Mosaic

Squash Leaf Curl Tomato Spotted Wild

Potato

Potato Leaf Roll Potato S Potato X

Potato Y Tomato Spotted Wilt

Spinach

Beet Curly Top Beet Mosaic Broad Bean Wilt

Cucumber Mosaic Tobacco Mosaic

Figure 2: Common Viral Diseases of Selected Agricultural Plants.

Note: This is NOT an exhaustive list.

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MAXIMUM YIELD UK - July / August 2010

Viral Diseases of Tomatoes Tomato leaf curl virus causes stunted growth and, as the name suggests, leaves that curl inward to give a puckered appearance.

Often the leaf edges are yellow. Flowers do not develop properly and fruit production is reduced. Whiteflies are the mode of transmission. The virus isn’t transmitted by infected seeds or pollen. Insect control is the key to prevention, by using chemical treatment or, for the organically minded, insect netting.

Cucumber mosaic virus has an unusually broad host range, able to infect not only cucumbers and tomatoes but also peppers, celery, beets, spinach, squash and even petunias. Leaves become distorted, with slight or spotty yellowing. The plants don’t achieve their expected stature and fruit production is inhibited. Aphids are a basis but contaminated materials can also be a source of the virus.

Some non-crop plants can also harbor the virus, so if it becomes a persistent problem, clearing weeds from the vicinity of the growing area may help to keep it in check.Virus resistant cultivars have been developed and should be used.

Viral Diseases of Potatoes Potatoes have become more important as a hydroponic crop in recent years; particularly minitubers, which are multiplied by farmers into seed potatoes, and in turn grown to marketable size. Unfortunately, potatoes are susceptible to more than 20 different viral diseases. Minitubers must be absolutely virus-free, because if the virus is propagated along with the minitubers and seed potatoes without detection until the final stages of production, the economic loss can be huge.

Tomato spotted wilt virus causes a disease in potatoes that can be hard to detect. The symptoms are variable. Plants can be stunted, or show necrotic spots on the leaves. This is one virus that can actually kill the host plant. Infected tubers may have concentric necrotic patterns on their skin, or they may show no outward symptoms at all. The disease is commonly vectored by thrips.

Minitubers destined for seed potato production must be guaranteed virus-free. Molecular methods are thus justified in testing tuber and leaf samples for the presence of viral proteins. A method called ELISA (enzyme-Linked immunosorbent assay) is often employed to screen hydroponic potatoes for viral diseases.

When plants show symptoms of a disease that doesn’t respond to the usual treatments against bacteria, fungi or insects, consider the possibility of a virus.You may have heard the phrase “there’s no cure for the common cold.” Colds are caused by viruses, and with few exceptions, we don’t have drugs to effectively combat viral infections. The same is true when it comes to viral diseases in plants. Prevention is the key. This is achieved by keeping things clean (tools, equipment and people), using reliable sources of seed and by controlling vector insects.

If a virus appears in your plants, don’t try to save them.There is no treatment. Infected plants must be removed and destroyed and no part of them can be allowed to come in contact with healthy plants. MY

References Sander, D., All the Virology on the WWW, http://www.virology.net/garryfavwebplant.html, accessed 05/12/08 Brunt, A.A., Crabtree, K., Dallwitz, M.J., Gibbs, A.J.,Watson, L. and Zurcher, E.J. (eds.) (1996), Plant Viruses Online: Descriptions and Lists from the VIDE Database,Version: 20th August 1996, http://biology.anu.edu.au/Groups/MES/vide/, accessed 05/12/08 The World Vegetable Center, http://www.arvdc.org, accessed 05/12/08 International Potato Center, http://www.cipotato.org/potato/pests_diseases/viruses/index.asp, accessed 05/13/08

MAXIMUM YIELD UK - July / August 2010

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Y L L A B O L G G N I W GRO

d l i W t s d a l i E W

s c i n o p o r e d h t Hy in

SIA

US aKA R

by Noucetta Kehdi A few months ago my husband William Texier—R&D, technical advisor and greenhouse director at General Hydroponics Europe (GHE)—and I travelled to Russia to better understand the hydroponic market, meet with retailers and visit hydroponic operations to offer help and advice.

Our first visit was with Denis, co-founder of Dgrow in Moscow, the first hydroponics store in Russia. The store featured a small garden with beautiful plants and fragrant gardenia flowers. We met Sergei, Dgrow’s gardener. Sergei has the green touch proven by his healthy and vigorous plants. William talked with the staff until after midnight, answering their questions and addressing their challenges.

The next day we visited The Greenhouse, the first hydroponic shop in Perm, located in the Ural Mountains. The manager Lisa is also the shop’s main grower and her work was impressive. The store is a small jungle full of luscious, vibrant plants and vines all growing hydroponically. Her passion and enthusiasm for hydroponic technology was evident. She understands the technology’s potential, and is especially interested in commercial applications.

The Perm region is very large with more than one million inhabitants. It is covered with snow from October to April. Promising ventures in this area include plant propagation, production and sales of fresh food and flowers.

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MAXIMUM YIELD UK - July / August 2010

Designing hydroponic home gardens is an excellent option It is one of the largest agricultural countries in the world. too, as there seems to be an increasing amount of modern Water is free in most areas, and electricity extremely cheap. houses built with the latest technology, and the owners love The climate is very rigorous and winters are harsh and long. the idea of gardening at home year-round in hydroponics.

A big part of Russian soil is not exploitable: too dry, too cold and lots of it is covered with tundra, taiga, steppe and forests.

Our next visit was to a large family farm, also in Perm.

Agriculture is only possible seven months a year in the bestThis family-owned farm operates a salad and herb adapted areas. Russian agriculture is confronted with its own greenhouse using hydroponic systems. We helped them limitations while demand for a larger variety and a better solve several of their challenges. Their plants looked good, quality food is increasing as fast as but they had a circulation/ the market economy is developing. oxygenation problem, and “ A big part of Russian soil is not Russia imports a tremendous they had planted too many exploitable: too dry, too cold and lots amount of food products and plants per pot. We ended up more than 75 per cent of that having tea and discussing the of it is covered with tundra, taiga, is fruits and vegetables. The different improvements to steppe and forests.” current farming organization isn’t make to their venture.

The last visit was to one of efficient enough and growers Perm’s outer neighbourhoods where we met Aleksander, the must modernize their infrastructure. In 2007, the Russian caretaker of a block of buildings where all the basements government approved a program to increase the country’s are empty and available for use. His plan is to start a small auto-sufficiency in edible crops, with special attention on strawberry farm, selling his produce in the neighbourhood durable development; employment expansion; improvement farmers’ markets to start. He had already converted some 20 of rural life conditions; reinforcement of Russian square metres into a growroom, with light and ventilation, and competitiveness; and conservation of natural resources. One was growing strawberries in an AeroFlo unit. However, the of the main focuses is to increase efficiency by adopting new leaves were a dark green and stressed, the plants had a poor durable technologies. And which technology would be better root system and there was a huge spidermite infestation. With than hydroponics? a few EC and pH corrections, his problems were quickly Hydroponics can be adapted to most environments; it can be corrected. Due to the environment in these old buildings, used in closed circuits and does not pollute the underground; we stressed the importance of healthy surroundings, free of it cuts back on water and nutrient consumption; it saves toxic elements that may be found in the building materials on transportation costs when grown on-site; it allows you and paint. We stressed the importance of general cleanliness, to grow more food on the same surface, and when done aeration, ventilation, lighting and prevention with integrated correctly, it allows you to grow a lot of quality food. Once pest management when possible. installed, there is little cost for maintenance between crops, In just a few days one can’t possibly grasp the situation of and hydroponic systems are durable. hydroponics in Russia, but it is not difficult to realize that This visit gave us a good perspective of how hydroponics there is a strong potential for hydroponics here. This is could be used in Russia. Each of our contacts there has a huge country: 142 million inhabitants plans to work on developing the market. We on 17 million square are here to help them reach kilometres. their goals. MY

Visit www.maximumyield.com and take a tour through Russia’s hydroponic market and enjoy the views.

MAXIMUM YIELD UK - July / August 2010

39

TALKING SHOP

AT A GLANCE Company: Brit Crops Ltd. Owners: Mark Ballard Location and Phone: Unit 9 Oj’s Industrial Park Claybank Road Portsmouth, Hampshire, UK Phone: 44 (0) 239-266-9111

Terry English

Web: www.britcropshydroponics.co.uk E-mail: info@britcropshydroponics.co.uk

rd Mark Ballaps Ltd.

ro Owner – Brit C

I

n 2009 the indoor gardening industry in the UK was up 27 per cent. At the time Mark Ballard was working as an electrical engineer designing control systems for industrial process machines. But his interest was in horticulture. He would’ve been crazy to not jump on the opportunity and take advantage of this growth in his field of interest. He didn’t wait; near the end of the year he took possession of a building for his business and in December 2009 he opened the doors of Brit Crops Ltd. to the public.

Growers took an immediate interest in the new grow shop and customers swarmed Brit Crops for products and advice.

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MAXIMUM YIELD UK - July / August 2010

“Mark’s product knowledge is expansive and he prides himself on being able to answer pretty much any question a customer brings forth.

As the sole owner and operator of the store, Mark has been run off his feet, but it’s exactly the environment he thrives in.

It can certainly be hectic at times and it is for this reason Mark accepted the help of a knowledgeable and eager friend, Terry English. Terry’s help around the shop has been significant and his interaction with the customers is akin to chatting with friends.

As one of three shops in the area, Brit Crops distinguishes itself by offering unparalleled advice and a variety of products that cater to many unique growing situations. In the near future, Mark will be adding exclusive product lines and modern technologies to further set him apart from his competitors.

Mark has taken ads out in the local newspaper, which have certainly helped promote the store, but his unique customer base is not being reached. The people that read Maximum Yield are the people Mark wants to reach with his advertising, and he predicts a significant growth with this targeted publicity. In addition, large billboard signs—digitally designed by Mark—are strategically placed around town and help direct new customers to the store.

As the customer base—and the business—grows, Mark has the opportunity to expand his square footage by moving into the unit next door, a space he acquired strictly with growth and expansion in mind.

This growth will allow Mark to further promote the grow room design side of his business. Mark has a special aptitude for converting empty spaces into fully functional and effective grow rooms with special attention to lighting and

ventilation. Mark’s knowledge of grow room ventilation puts him ahead of the competition as growers in Britain are always looking for fresh ideas, particularly during the hot UK summers.

Brit Crops carries all the indoor gardening and hydroponic essentials and if they run out of a product in one brand, they always have an alternative option or brand on hand.

Mark’s product knowledge is expansive and he prides himself on being able to answer pretty much any question a customer brings forth. All he knows he learned through experimentation, research and lots and lots of reading.

As a relatively new shop, Mark has been impressed with the store’s success in the past six months. The future of Brit Crops and indoor gardening in general, looks promising.

The recession—which was at its worst ever last year since the 1960s—has Britons taking matters into their own hands, growing at home. Mark’s patience has really been tested waiting for his business to grow, but now that it has, he has been able to focus his energies on being optimistic and proactive.

MY

MAXIMUM YIELD UK - July / August 2010

41

g n i t n e v Pre o t g n i t c a e R and

Green Algae

by Matt LeBannister

There are many problems gardeners face, beginner and advanced growers alike. Most advanced gardeners have faced the annoyance of algae growing in their reservoirs and rockwool cubes. There are over 6,000 species of algae and they range in colour from brown, to green, to red, etc. Green algae are the most common algae that will invade indoor gardens, especially hydroponic gardens. Green algae will rob nutrients from plants and will clog pumps, sprayers and drippers of hydroponic systems. Many insects and their larvae also feed on green algae and can lead to bigger problems and infestations. Beginners, when faced with the problem of preventing and reacting to algae, may feel lost and overwhelmed by the situation.

Prevention, such as cleaning equipment between crop rotations, is the best way to keep a garden safe from this growroom pest. Most types of algae need nutrients, light and a moist environment. The easiest way to prevent algae from growing is to stop light from entering reservoirs, N.F.T. tunnels, grow cubes and any other surface that is moist and containing nutrients. The best way to block light out of reservoirs is to keep it covered by a lid. If a lid is not available lightproof plastic is a suitable solution. The best lightproof plastic is white on the outside to reflect light away and black on the inside to absorb any light rays that might get through.

This same process can be done to cover hydroponic tables to keep algae from growing on cubes and roots. The simplest way to do this is to stretch the black and white plastic tight across the hydroponic table before placing the rockwool cubes, mesh pots or whichever growing medium your clones or seedlings will be transplanted into. Once the plastic is stretched over the medium, a small cut can be made so the plant can

be transplanted with minimal damage to the plastic. This way as little light as possible will reach the medium and rootzone preventing any algae growth there.

To control the outbreak of green algae use hydrogen peroxide (H2O2). This is added to reservoirs in hydroponic systems or added to nutrient solutions as part of a top watering routine. Hydrogen peroxide will corrode algae to kill them, but this must be used with every watering to be effective. When peroxide comes into contact with algae and other undesirables in the water, an oxygen molecule will break off and bond to the algae. When there are no more algae left to bond to, the extra oxygen molecule will still break down and provide oxygen to the roots. After the oxygen molecule breaks off of the compound hydrogen peroxide (H2O2,) you are left with water (H2O).

One must take care when using hydrogen peroxide, because it is highly corrosive. Wear eye and hand protection when applying to be safe. Hydrogen peroxide can also damage young roots and should not be used on seedlings or clones.

There are many products known as algaecides that are available to combat algae infestations, but they are not recommended.

These algaecides are dangerous to plants, because the active ingredients used to combat the algae can also destroy healthy roots and plant tissue. The potential benefits of algaecides are not worth the risks they pose to the healthy plants they are meant to protect.

Green algae infestations are a constant nuisance once they infiltrate growing mediums and hydroponic systems. By taking protective measures against algae gardeners can prevent the problem from ever starting.

MY For more articles by Matt LeBannister visit maximumyield.com and search our author archive.

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MAXIMUM YIELD UK - July / August 2010

DO YOU

know?

1

2 3

4

If you can decide on a soil or medium mix that suits your needs, you can custom create your own with the help of a knowledgeable sales clerk at your local grow shop.

The newest generation of LED lights will run for at least 50,000 to 100,000 hours, or the equivalent of 10 years, before needing to be replaced.

5

In the early days of vertical gardening, systems consisted of long, thin tubes of growing media such as sawdust that were suspended from overhead rails.

6 7

The internal circuitry cooled with several small computer-type fans, is the component in secondgeneration LED lighting systems that make them slightly heavier than first-generation systems.

8

Most organic biostimulants are at their best when combined with fertilizers. Their low nutrient content makes them less effective when used alone.

In Russia there are 142 million inhabitants living on 17 million square kilometres.

Vertical systems that rotate help eliminate problems with shadows and uneven illumination so that lighting is used even more efficiently.

Biostimulants have been shown to influence several metabolic processes such as respiration, photosynthesis, nucleic acid synthesis and ion uptake.

MAXIMUM YIELD UK - July / August 2010

43

YOU TELL US

Maximum Yield talks to Wim Schinkel of Plagron, Dutch nutrient manufacturers, about the various grow concepts and styles, products tailored for the urban hydro grower and natural products that pack a powerful punch.

Maximum Yield (MY): What do Plagron’s various grow concepts entail and what do they mean for growers?

Wim Schinkel: The Plagron concepts— which include The Terra Concept, The Bio Concept, The Cocos Concept and the Hydro Concept—entail everything you need to get maximum yields and healthy plants from cutting to harvest for each unique growing style. The grow concepts serve to help simplify each unique growing process. The various concepts, and corresponding products, contain everything you need to grow with no additional supplements required.

MY: What products do you carry for the urban hydroponic gardener and what ingredients do they contain?

Wim: Hydroponic gardeners in urban regions can experience great difficulties with some of the available substrates because of their large size or heavy weight.

In response to this challenge, Plagron has developed the Hydropack especially designed for urban hydro gardeners.

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MAXIMUM YIELD UK - July / August 2010

MY: Describe the ecofriendly qualities of the Plagron Roots product.

The Hydropack contains nutrients in the highest concentration possible. For the grower this means a low quantity of nutrients resulting in a great quantity of plant nutrition. The Hydropack has been designed in such a way that no substrate at all is needed. Therefore, for urban gardeners the Hydropack is the ideal combination.

Because no substrate is needed the demand for a stable nutrient is higher than normal. This is the main reason that the Hydropack is fully chelated. This will result in contact availability of nutrients without the risk of deposits forming.

Wim: Plagron Roots is the ideal combination of fresh seaweed extracts combined with vitamins, natural hormones and trace elements. This combination ensures stimulation in root development that growers have never seen before. As all ingredients are 100 per cent biological, our stimulator is 100 per cent environmentally friendly and gives you a 150 per cent results.

MY: What plant processes are supported by your new bloom stimulant Green Sensation?

Wim: The new Green Sensation is the successor of the old formula. We have

taken all the positive active ingredients of the old Green Sensation and added some new ones for the new and improved Green Sensation.

Positive effects include: • increased flower formation • 100 per cent increased active ingredients (plant sugar, etc.)

• increased plant weight MY: Your line of liquid and solid organic fertilizers includes many sea inoculants and emulsions plus worm castings, guanos and blood meal. What are the benefits to these

will result in a healthy, stress-free plants with improved flavour versus the plant being fed with chemical fertilizers.

MY: What products do you carry that would ideally suit the grower just starting out?

Wim: That would be our 100 per cent organic potting soils (Plagron All-mix, Bat-mix and Royalty-mix). These mixes carry sufficient biological nutrients to help raise the plant from a seedling to a healthy “grown-up.” The only action required by the grower is to water his or her plants.

natural fertilization methods?

Wim: If you use the products mentioned above you are feeding and stimulating nature with pure nature. If you choose organic and natural products you will supply the plant with all its needs. This

MY: Where are Plagron products available?

Wim: Plagron products are available in all hydroponic shops in the UK and Ireland.

For further information and a map of retailers please visit www.plagron.com MY MAXIMUM YIELD UK - July / August 2010

45

PRODUCT spotlight

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

Continued from page 17

Plant Magic Plus Nutrients ____________________________________________________ Plant Magic Plus nutrients are new to the market place, but don’t let that fool you with their performance. These nutrients are manufactured in the UK specifically for UK horticulturists. The very best quality ingredients are used to ensure maximum uptake and availability directly to the plant.

As well as having better tasting fruit crops with more aroma and a noticeable increase in yields, hydro and coco growers will find that their pH will be a lot more stable. Too much phosphoric acid is not good for humans or our plants.

All nutrients are available in one litre, four litre and 18 litre containers. Distributed via Plant Magic Plus and Nutriculture at your nearest indoor gardening store.

Keep It Clean Drip Cleaner New from DutchPro _______________

Penetrator LED Grow Lights from Hydro Grow LED _______________________

Keep it Clean keeps your drip system spotless, particularly when using tap water.

This plant-friendly cleaning agent prevents and removes algae, bacterial slime and delays the growth of fungi. Suited for every irrigation system. Use 10 millilitres per 100 litres of water. Available in one litre and five litres. Keep it Clean is stable and clear; contains organic elements; keeps plants vital and green until the end of the cycle; and enhances plants’ taste and fragrance. Ask for Keep It Clean at your local hydro shop today.

Hydro Grow has fixed all of the conventional problems our competitors are still experiencing with LEDs. The spectral outputs from our Penetrator LED Grow Lights match all four chlorophyll absorption peaks required for photosynthesis, guaranteeing the highest possible conversion rate from electrical energy to plant energy, with little to no energy wasted. Our products deliver this light more efficiently to your plants vs. any of our competitors, by using a unique 60° lens. Our lens distributes light at four times the intensity of their 120° lens, which enables full penetration comparable to HID. Without full penetration the rate of light absorption is much weaker, resulting in slower growth rates and lower yields. Independent grow tests have proven our LED Grow Lights to be at least 60 per cent more efficient when compared with HIDs, and up to 70 per cent more efficient than our competitors’ LEDs. Experience for yourself the world’s most efficient horticultural grow light!

Available now at your local indoor gardening store.

Hortilight Plasma Lighting System _________ Introducing the new plasma grow light by Hortilight. The revolutionary Plasma Lighting System is a new light source with the highest affectivity and a true, full spectrum similar to sunlight. The visible light output mimics sunlight better than any other artificial light source. The specially tuned Hortilight Plasma light delivers very little heat compared to HPS and a lack of harmful ultraviolet radiation makes it the most efficient grow light available. Test results are very clear; young cucumber plants became 64 per cent heavier (dry weight) under Plasma sunlight and 128 per cent heavier then under fluorescent light.

Ask for the Hortilight Plasma Lighting System today at you favourite indoor gardening shop.

48

MAXIMUM YIELD UK - July / August 2010

MY You can find all of our products online at www.maximumyield.com. 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 editor@maximumyield.com

CHECK YOUR growing I.Q.

by Erik Biksa

Q

1. Why is it important to keep the root zone at optimal temperatures during warmer and hot growing conditions? a) To prevent root pathogens from infecting the crop. b) To help in achieving maximum yields. c) To promote healthy aerobic microbial growth. d) all of the above 2. What measures can be taken to help keep the roots at optimal temperatures? a) In re-circulating systems, a cooling soil can be placed in the reservoir, or an inline chiller may be installed. b) Organic based soilless mediums and potting soils can be used in large containers or raised beds. c) Air-conditioning can be incorporated into the growing environment to keep ambient temperatures down. d) For re-circulating systems, the reservoir can be kept outside the grow room or insulated from the growing environment 3.Why is increased aeration a good idea for recirculating systems during warmer and hot periods?

4. Why are smaller profile lamp reflectors more advantageous during warmer growing conditions?

ANSWERS: May/June 2010 quiz

5. Is variety selection an important factor when dealing with high growing temperatures? a) Yes, some varieties will actually produce better in tougher, hot growing environments. b) No, all the different strains a plant species prefer similar conditions.

6. Why do spidermites become especially problematic in warmer growing conditions? a) Their alcohol consumption increases. b) They are able to reproduce faster; life cycles are shortened. c) They are more temperamental when sunburned. d) none of the above

A

1) a, b, c 2) a, b 3) d 4) a, b, c 5) plant and microbial derived sources: the molecules are more familiar to the plant due to evolution and environment 6) b answers to this quiz will be printed in the September/October 2010 issue of Maximum Yield.

MAXIMUM YIELD UK - July / August 2010

49

MAX-MART

COMING UP IN september-october 2010

MAXIMIZE YOUR EXPOSURE WITH

MAX-MART

Get your Max-Mart ad into the next issue!

Call Maximum Yield at (250) 729-2677 for more information.

Strong and Sweet

With over 60 varieties available and a myriad of health benefits, there’s no reason not to grow basil.

And best of all, most varieties are adaptable to organic cultivation and grow easily indoors.

Nature Supporting Nature Better understand the natural media options

available for hydroponic applications taking into consideration cost, biocompatibility, availability and disposal.

The Flavour Wheel Enhance the distinctive flavour of your crops by

exerting control over nutrition—and other factors— for the ultimate taste experience.

UK Exclusive Competitions Give your grow the best with products from top UK

manufacturers in our Win Big…Grow Big competition.

Enter online at maximumyield.com/winbigUK throughout the year for your chance to win, and keep reading Maximum Yield UK for more information on this and other giveaways.

Upcoming international events, exclusive contests, latest industry news, reader question and answer, best products and technologies, and much, much more.

Maximum Yield UK (September/October) will be available September 1 for FREE at selected indoor gardening retail stores across the UK and on maximumyield.com. Subscriptions are available at maximumyield.com/subscriptions.php

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UK July - August 2010

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