CONTENTS 1
INTRODUCTION
3
6
What Is Hydroponics?
HYDROPONIC GROWING SYSTEMS
7
How to Choose a System
Advantages of Hydroponic Growing
8
Key Features of a Hydroponic System
Bottle Hydroponics 13
Floating Rafts Wicking Bed
2
Media Beds
18
19 23
Aeroponics
Substrates and Growing Media
24
Equipment for Growing Indoors
28
Grow Lights
92 99 115
156
146
Flushing
160
Cleaning
161
157
148
7
5
COMMON PROBLEMS
PLANT NUTRITION
Fertilizers
SYSTEM MAINTENANCE
Managing the Nutrient Solution
69
Plant Nutrient Uptake
106
Vertical Gardens
136
142
Transplanting Plants Started in Soil 83
6
138
Rooting Cuttings in a Hydroponic Cloner
60
Flood and Drain
Pots and Trays
STARTING SEEDS and CUTTINGS
Rooting Cuttings in Stone Wool
50
Top Drip System
38
Starting Seeds in Stone Wool
42
Nutrient Film Technique (NFT)
EQUIPMENT
Irrigation
39
4
150
and TROUBLESHOOTING
151
Nutrient Deficiencies
152
Measuring Fertilizer Concentration
Infestations 154
162
163
166
Seedling Problems
168
29
Pest Management Products and Equipment Meters
35
32
Glossary
170
Appendix: Crop Selection Charts Metric Conversions
186
Resources and Photo Credits Index
188
About the Author
172
192
187
CONTENTS 1
INTRODUCTION
3
6
What Is Hydroponics?
HYDROPONIC GROWING SYSTEMS
7
How to Choose a System
Advantages of Hydroponic Growing
8
Key Features of a Hydroponic System
Bottle Hydroponics 13
Floating Rafts Wicking Bed
2
Media Beds
18
19 23
Aeroponics
Substrates and Growing Media
24
Equipment for Growing Indoors
28
Grow Lights
92 99 115
156
146
Flushing
160
Cleaning
161
157
148
7
5
COMMON PROBLEMS
PLANT NUTRITION
Fertilizers
SYSTEM MAINTENANCE
Managing the Nutrient Solution
69
Plant Nutrient Uptake
106
Vertical Gardens
136
142
Transplanting Plants Started in Soil 83
6
138
Rooting Cuttings in a Hydroponic Cloner
60
Flood and Drain
Pots and Trays
STARTING SEEDS and CUTTINGS
Rooting Cuttings in Stone Wool
50
Top Drip System
38
Starting Seeds in Stone Wool
42
Nutrient Film Technique (NFT)
EQUIPMENT
Irrigation
39
4
150
and TROUBLESHOOTING
151
Nutrient Deficiencies
152
Measuring Fertilizer Concentration
Infestations 154
162
163
166
Seedling Problems
168
29
Pest Management Products and Equipment Meters
35
32
Glossary
170
Appendix: Crop Selection Charts Metric Conversions
186
Resources and Photo Credits Index
188
About the Author
172
192
187
Circular plastic pots are generally the easiest to find. Square plastic pots can help maximize the space in a hydroponic garden by removing all gaps between pots. Square pots are a popular option in grow trays because they can be packed in tightly. Grow bags have been used in commercial farms for a long time and are starting to make their way into home gardens. They can be difficult to reuse, but they are definitely one of the cheapest options for a pot. The side walls of grow bags can be rolled down to adjust the volume of the pot. Although the bag may look square when A ½" elbow connector
A ½" tee connector
empty, it fills out to be a cylinder.
A ½" stopper
Fabric pots are great for hydroponics because they are quick draining but don't have large holes that can possibly let out substrate. They are perfect for flood and drain systems because it is easy for the water to soak into the substrate and then drain
Flood and drain combo kit
quickly. Fabric pots are easy to reuse too! Simply empty out the substrate, turn the bag inside out, let it dry, and brush off any remaining debris. They can even be put in a A 12" circular pot
washing machine for a deep clean. Terracotta pots are not commonly seen in hydroponics, but that doesn't mean they can't be used. Terracotta pots used in gardens are porous, allowing air and water to pass through the walls, traits similar to a fabric pot. Unlike a fabric pot, terracotta is
Ball valves (or shutoff valves) restrict or
heavy and fragile.
stop flow. They are useful for balancing A ½" rubber grommet
flow in NFT and vertical hydroponic gardens
An irrigation line hole punch is used to create
that may have multiple irrigation zones with
small holes in ½" or ¾" vinyl tubing for the
various flow rates.
insertion of ¼" barbed connectors.
Square pots are great for using space efficiently.
Fittings Flood and drain fittings allow DIY gardeners to create their own flood trays from household materials like plastic storage totes. Generally, these fittings come in a set that includes a ½-inch fill fitting, a ¾-inch drain fitting, extensions, and two screen fittings. Grommets are one of the most useful irrigation fittings in DIY hydroponics. Grommets create a watertight seal around irrigation fittings. They can transform
Low-cost grow bag
PVC pipes, plastic totes, buckets, and more into hydroponic growing areas or reservoirs. Commonly available in ½ or ¾ inch. Tubing connectors function and look very much like the plumbing connectors that anyone with experience doing home plumbing is accustomed to using (except, of course, that they are much smaller).
POTS AND TRAYS Net pots can be square or circular and generally range from 2 to 10 inches wide. This book focuses on uses for 2- and 3-inch net pots, the most commonly used net pot sizes in DIY hydroponic systems.
22 DIY HYDROPONIC GARDENS
Flexible fabric pot
Classic terracotta pots
Equipment 23
Systems with a high plant-to-water ratio also tend to accumulate an imbalanced ratio of nutrients and require frequent full system flushes. Another factor that will influence maintenance requirement is crop selection. Crops like tomatoes, peppers, and cucumbers may require trellising and pruning depending on variety. Some crops grow very quickly and need to be replaced often, like microgreens, and they'll require a lot of work because they need to be seeded and harvested weekly.
Choosing a System by Difficulty Although I would never stop someone from starting with an advanced hydroponic system, I am aware that many gardeners want to succeed from the start. Difficult-touse systems may have a learning curve. I love learning! You might too. But you also might value simplicity and using a hydroponic system that has minimal moving parts and few opportunities for failure. Bottle Hydroponics, Floating Rafts, and Wicking Beds are great beginner-friendly systems that don’t require electricity. Media Meds and Flood and Drain are also beginner friendly, but they have some moving parts that require electricity. Nutrient Film Technique, Top Drip, Aeroponics, and Vertical Gardens are not terribly difficult, but they might not be the best option for a first-time hydroponic gardener. The difficulty of using a system is a personal opinion and it’s possible you might find some bottle garden. This system works great for leafy green crops like lettuce and basil,
Degree of difficulty is a
of the less beginner-friendly systems easiest to use . . . The only way to find out is to
but is horrible for larger crops like tomatoes. You should also consider the diversity
primary consideration when
build them all!
of crops you want to grow. Do you want to grow crops with a wide range of nutrient requirements and desired pH ranges? The best option sometimes is to have multiple systems. The best part about growing plants is that they are generally easy to replace! Experiment with new crops and learn from experience. I offer a lot of guidelines in this chapter and useful crop selection notes in the appendix, but these guidelines are not meant to prevent you from experimenting. Many crops will grow in conditions outside of their ideal range. Plants are far more tolerant than we give them credit for. Don't be afraid to fail; there are always more seeds to plant!
Choosing a System by Location There are hydroponic systems for growing lettuce in space! No matter your location, there is potential to grow plants hydroponically. I even have a hydroponic garden in my
choosing a hydroponic system. This recirculating trough system is relatively simple to make but requires regular monitoring and maintenance.
Featured DIY Hydroponic Systems On the following pages you will see many of my favorite DIY hydroponic systems explained and built before your eyes. Along the way I have tried to give reasons why you might choose one system over another. Before you decide which one (or ones) you want to make for yourself, I suggest that you read through all the builds so you fully understand the pluses, minuses, and degree of difficulty of each system.
• • • •
BOTTLE HYDROPONICS FLOATING RAFTS WICKING BED NUTRIENT FILM TECHNIQUE (NFT)
• • • • •
TOP DRIP SYSTEM MEDIA BEDS FLOOD AND DRAIN AEROPONICS VERTICAL GARDENS
RV. For each of the systems listed in this chapter I give location suggestions. Many of these systems can be modified for indoors, outdoors, small spaces, or large ones.
Choosing a System by Maintenance Requirements The ratio of plants to volume of water is generally the biggest factor for estimating maintenance requirements. A system with a small reservoir and a lot of plants will need frequent maintenance because the grower will need to add water and amend the reservoir with fertilizer as the plants quickly reduce the water level in the reservoir.
40 DIY HYDROPONIC GARDENS
Hydroponic Growing Systems 41
13
15
19
18
12 Position these 2'6¾" boards on top of the reservoir. Position the 2 × 6" × 4' boards on top of these, running the length of the reservoir. These will be used
19
to guide the positioning of the support legs. 13 Use the square and level when fastening the support legs to the reservoir. It is very important that these legs are straight upright and not leaning. Use two 2½" screws to secure the legs into position. 14 Fasten the 2 × 6" × 4' boards to the support legs. The top edge of the 4' boards should be flush with the top of the legs. 15 Mark the position for the 2'6¾" crossbeams. The high end of the NFT channels will go through a crossbeam 5¼" from the end of the 4' boards and the low end of the NFT channels will go through a crossbeam 6¼" from the other end of the 4' boards. 16 Arrange the 2'6¾" crossbeams so one side has the drilled holes toward the bottom and the other side has the drilled holes toward the top. Fasten the crossbeams with only one screw near the top of the frame. It will be important to have the ability to adjust the angle of this board when inserting the PVC channels. Later they will be secured into place with a second screw.
16 17 Insert the 3'7" PVC segments into the crossbeams. These will be the growing channels. 18 Attach the manifold to the 3'7" PVC channels. The ¾" drainage elbow should be on the lower side of the manifold. Do not glue it yet. 19 Mark the placement of the net pots in the channels. The net pots in this design are 6" apart within the channel and are arranged in a checkerboard pattern to create Crossbeam with drilled holes near the bottom
76 DIY HYDROPONIC GARDENS
Crossbeam with drilled holes near the top
additional space between plants from neighboring channels.
Hydroponic Growing Systems 77