HYDROPONICS

“Hydroponic garden-

ing is a dirt-free, low-

cost, space saving,

low in pesticides,

and environmentally

friendly way of grow-

ing plants without

any soil.”

- Rick Helweg

In This Issue

Hydroponic systems

Perfecting your sys-

tem

Nutrients

Growing Media

Company profile:

Young Family Farm

Company profile:

Ecobain Gardens

Microgreens growing hydroponically at Ecobain Gardens

The future of food Hydroponic gardening allows you to be in complete control of

growing food: from the nutrients your plants uptake, to the environ-

ment they’re growing in. Growing hydroponically is truly the com-

plete definition of precision agriculture.

Hydroponic facts 90% less water than the same crops in conventional gardening

Takes up 1/4 the space of conventional gardening

Perfectly balanced pH, highly oxygenated water, continuously

available for optimum growth

Half the growing time for some crops

Low or no pesticide and herbicides

Lil Em’s Garden Publications May 2015

Hydroponic Systems

Before understanding

how to manage a hy-

droponics system it is

important to know all

of the different systems

in hydroponic gardein-

ing.

Each system is unique,

but they all have one

thing in common: they

don’t use soil, the

plants get the elements

they need from the nu-

trient solution, which is

available for the plant

continuously.

NFT hydroponics in Mount Vernon, MO

Nutrient film technique An advanced hydroponic system primarily used for commercial

growers, the NFT (nutrient film technique) system is effective in

many crops, especially leafy greens and herbs.

The NFT system is classified as dynamic due to the recirculation of

the nutrient solution. The

nutrient solution is

kept in a separate res-

ervoir where it is

returned after being

cycled through the

inclined PVC pipes

for as long as the water

and nutri- ents are via-

ble. The steady stream of water is shallow as to provide nutrients

continuously without drowning the roots, which can lead to root rot.

Raft systems Another common approach for growing lettuce, herbs, and other small leafy plants is the raft system. The

plants are suspended above the nutrient solution in small net cups, held afloat with a Styrofoam raft.

The seedlings should be started in the growing media that will eventually hold the roots together at the

base of the plant. Cornell University recommends transferring the seedlings to a raft with closely spaced

holes (97 plants m-2), then again after 21 days to another raft with adequate space between the holes (38

plants m-2).

Maintaining your system

After each raft has completed one growing season it is recommended to disinfect with a 2% bleach solu-

tion. It is also important to rise your entire solution out when it is no longer viable. The water can be recy-

cled by using it to water/fertilize soil gardens. There are many products available to rinse through your sys-

tem, such as Bonticare’s ClearEx, however some people simply use water.

Cornell University’s set specs

Bibb lettuce is the most common crop grown by commer-

cial growers. The optimal settings are published by Cornell

University in their Hydroponic Handbook. The ideal pH is

between 5.6-6, and should be checked regularly to main-

tain healthy growth. Relative humidity should not exceed

70% and not fall under 50%.

Smaller spacing for 11-21 days

Raft hydroponic system in California

Top-drip bucket system This hydroponic system is the most complicated of all the bucket

systems. It is more of a dynamic system because the nutrient solu-

tion is fed from a top flowing drip line. There is a return drain that

allows access water to return to the reservoir to be recycled through

continuously.

The grow media that is most common in top-drip bucket systems

includes clay pebbles and perlite. Because of the excellent draining

qualities of these porous medias, there is not a need for an air stone

or air pump. The roots receive enough oxygen through the spaces of

the media, despite the steady stream of water coming from the drip

line. The water won’t become stagnate due to the constant stream,

which allows aeration for the roots.

What to grow

Top-drip bucket systems provide the opportunity to grow a large

range of plants. It works very well for houseplants as well as larger

vegetables, including tomatoes, as long as you are sure to allow a

big enough bucket to support the root system.

More bucket systems Also known as “deep water

culture,” bucket systems are

known for having a much

deeper reservoir than other

hydroponic systems. There

are several different kinds of

bucket systems.

The bubbler bucket system

includes a five gallon bucket

with a lid, a grow pot, an air

stone, and an air pump. This

system does not need a nu-

trient pump, as the roots are

partially submerged into the

reservoir.

Another system is the “no

pump” bucket. It is a very

simple system and requires

the least amount of materi-

als. All you need to get start-

ed is a bucket, perlite (or

another porous media), your

nutrient solution, and a PVC

pipe. It is also very easy to

maintain and grow fruits,

vegetables, or houseplants.

Clay pebbles and oasis cube media

An overview of the top-drip bucket system

Visual diagram of the Wick system components

Wick systems Another simple hydroponic system that is easy for at-home gardening is the wick system. Un-

like the previous systems, the nutrient solution is never directly connected to the plant’s roots,

which makes it more similar to conventional gardening. It does not require a pump, or any

moving parts, although an air pump may be used for more complex wick systems. The free-

dom from using a power source definitely has advantages, and helps keep growing costs low.

Growing media for wick systems

The most important quality for the wick growing media is that it is a good balance between

absorbent and well-draining. The most commonly recommended options include vermiculite,

coco fibre, and peat moss. The media needs to be absorbent so that the nutrient solution can

successfully get to the roots. However, the roots can become waterlogged very quickly if it

does not have good drainage.

Wick materials

Some wick systems allow part of the media to be in contact with the reservoir, which acts as

the wick. Other systems utilize cloth strips or cotton rope as the wick.

Ebb-and-Flow system

This complex hydroponic system is also known as the “flood-and-

drain” system. The most crucial part is the pump, which is connect-

ed to a timer. The timer is set to send the nutrient solution into the

grow tray, or drain pan, and then sends the overflow back into the

reservoir.

A common way of describing this system is the “tidal effect.” This

system is the most common for advanced hydroponic growers due

Aeroponics system Aeroponics is its own cate-

gory of hydroponics, be-

cause the nutrient solution is

used in a completely unique

way. Instead of dripping,

flooding, or flowing, aero-

ponic systems mist the

plants with the nutrient solu-

tion.

The plants are suspended in

the air, held together with a

growing media such as oasis

cubes, and placed in mesh

pots. A timer triggers the

pump to mist the roots dur-

ing specific intervals

throughout the day.

Aeroponics system diagram

The difference between pump on and pump of the ebb-and-flow system

Best fish for Aquaponics

Many different kinds of

fish are used for aqua-

ponics, from fish used for

meat or decorative fish.

Tilapia are one of the

most common species of

fish for aquaponics. They

are relatively easy to care

for, and have credible

success for being benefi-

cial to the plants.

Trout are another com-

mon fish used for colder-

weather aquaponic grow-

ers. Other common spe-

cies include catfish, koi,

salmon, and silver perch.

It is important to monitor

the temperature of the

fish tank, as each species

has an optimal range for

health.

Fish tank on left, hydroponic plants on the right.

Aquaponics Aquaponics combines aquaculture, or the farming of fish, with hy-

droponics. It is the best of both worlds, as they benefit from each

other. The fish provide a natural and organic nutrient solution for

the plants, while the roots filter the water, which can be returned

back into the fish tank.

Aquaponics can be done on a small scale for the home grower, but

is becoming increasingly popular with commercial growers for a

multitude of benefits. The grower saves money by not having to

buy expensive nutrient solution for the plants. They also benefit

from having two separate cash flows in one system. The fish are

sold either as a decorative fish or pet, or for their meat, and the

plants are sold as organic produce or beautiful house plants.

Many growers choose to build their aquaponic systems themselves,

as aquaponic set-ups can become quite expensive. However, some

aquaponic system companies provide a class on how to be a suc-

cessful aquaponic farmer.

Freshly planted seeds starting off under lights

Perfecting your system The options are endless for creat-

ing your hydroponic system.

From the many different systems

available, to the choices of nutri-

ents to add to your solution, to

the different media you can use.

When it comes down to it, per-

sonal preference is a huge factor

in deciding which options to use.

The biggest factor in setting up your hydroponic system is deciding what you want to grow. Certain

crops will grow better with specific systems, media, and might require different nutrient solutions.

Once you’ve found the plant you’re passionate about growing yon can choose to perfect your system

based on which conditions your crop prefers.

The next three pages will help explain the nutrient solutions for hydroponic gardening, and compare

and contrast the difference between media choices.

Questions to consider

Who are your customers?

Will you sell at farmer’s

markets, restaurants, or gro-

cery stores?

Where will you be growing?

Indoors, in a hoop house or

high tunnel, or in a perma-

nent greenhouse?

Will you use natural light, or

artificial light, such as LED?

Do you plan on growing year

-round? If so, do you have

the ability of providing a cli-

mate-controlled environ-

ment?

Essential Elements

Macronutrients:

These elements are re-

quired most by plants

for healthy growth. The

macronutrients include:

nitrogen, phosphorus,

potassium, calcium,

magnesium, and Sul-

phur.

Micronutrients:

Elements that are cru-

cial for plant growth,

but in trace amounts.

The micronutrients in-

clude: zinc, iron, man-

ganese, chlorine, cop-

per, nickel, boron, sili-

con, and sodium.

Germinated cilantro seed freshly transferred to an NFT system

Nutrient solution The nutrient solution is a term to describe the mixture of water and

water-soluble nutrients critical to the plant’s growth. There are

many ready-made nutrient concentrates available to purchase from

the store, however some advanced hydroponic growers prefer to

mix their own according to their crop’s specific needs. It is im-

portant to learn how to measure the pH and electrical conductivity

(EC) of your nutrient solution. EC is used to measure the potency of

minerals in your solution due to the electric current these elements

give off once dissolved in water. The most

common way of testing your solution is by

using a special pen that can read the electrical

current. Growers try to aim for an EC reading

within the 800-1200 range. Readings should

be taken twice, once in the reservoir holding

the solution, and once near where the solution

is coming into contact with the roots.

Taking an EC reading

Growing Media

The purpose of hydro-

ponics is to provide

nutrients for your

plants in the most effi-

cient way, through wa-

ter. This is why media

is selected based on

how it holds the roots

at the base of the plant,

and how absorbent and

porous it is; not on

providing nutrients for

the plant. The growing

media simply helps

support the plant struc-

turally, not nutritional-

ly.

Cilantro seedling in an oasis cube

Oasis cubes

Oasis cubes are extremely versatile and a popular choice for many

different hydroponic systems. They can be used alone as the prima-

ry growing media (especially in NFT and raft systems), or paired

with another media (for systems such as the top-drip bucket). These

cubes come in a large sheet for starting seeds, and can be broken

apart when the seedlings are ready to be transferred to the hydro-

ponic system. They are very absorbent, but still are 20% air when

completely saturated, which allows the roots to have enough oxy-

gen. These cubes are very similar to a florist’s foam and can be rel-

atively cheap when bought in bulk from a wholesale horticultural

supply company, such as Hummert International.

Rock wool

Rock wool is an inorganic media which is also very versatile and

can accommodate many different hydroponic systems. Rock wool is

created by heating rock and spinning it into fibres once it is molten.

It is used in the same fashion as oasis cubes, and can be the primary

source for your growing media, or used in conjunction with another

media. Rock wool is another relatively inexpensive material, how-

ever it will not biodegrade even though it is made from natural re-

sources.

Sphagnum moss

Moss is a common organic material, commonly used as a soil addi-

tive. It is not an expensive option for hydroponic media, but works

best when mixed with a porous media like perlite. A downside to

using sphagnum moss is it can clog pumps and hoses in the more

complex hydroponic systems.

Coconut Fibre

An increasingly popular organic

growing media, coconut fibre,

also known as coir, is the out-

side of a coconut shell and is

biodegradable. It is absorbent

and allows the roots to get

enough oxygen. It can also be

used as a mix with perlite. How-

ever, coir can clog pumps and

other moving parts in complex

hydroponic systems.

Perlite

Perlite is an extremely porous media that is great on it’s own, or used as a mix with organic materials to

increase aeration. Perlite is not a recommended media for ebb-and-flow systems, NFT systems, or raft sys-

tems due to its loose nature; however it is a great media for bucket systems and wick systems. Perlite is an

inorganic material often compared to vermiculite. Perlite is very dusty and it is recommended to wear a

dust mask when working with pure perlite for extended periods of time.

Vermiculite

Vermiculite, like perlite, is a common soil additive that is also the choice of media for a lot of hydroponic

gardeners. It is made from a natural mineral, mica, and is processed to make a particle that is sponge-like.

It is more absorbent than perlite, and shouldn’t be used on its own, otherwise the roots will have aeration

problems. It too is a very dusty media, so precautions should be taken for those with sensitivities to dust.

Vermiculite can also clog moving parts in a hydroponic system.

Expanded Clay

This media is popular with growing larger plants hydroponically, especially in bucket systems. Expanded

clay, also known as Leca, is available in different sizes for different growing needs. These man-made peb-

bles are from porous clay, and does not hold water on it’s own. Expanded clay can be an expensive initial

cost, however it is reusable, and can be simply sterilized between uses with a dilute bleach solution.

Gravel

Smooth gravel is a great media that can be used in the same situations as expanded clay. Because it’s very

heavy it wouldn’t be a good media for raft systems because it would sink the Styrofoam. It is important to

know what kind of rock you’re working with, as some rock, such as limestone, can affect the pH of your

nutrient solution.

Perlite and oasis cube media Three oasis cubes that will be separated soon

Company

Profile

Jesse Young graduated

from Missouri State

University in 2010 with

an Agricultural Busi-

ness BS. He started

Young Family Farm in

2012, and produces

around 1,400 pounds of

lettuce per week in his

two hydroponic green-

houses.

NFT hydroponics in Mount Vernon, MO

Young Family Farm Jesse Young, founder of Young Family Farm, started his own hy-

droponic greenhouse just two years after graduating from Missouri

State University with a BS in Agricultural Business. His farm is

right on the outskirts of Springfield in a small Missouri town called

Fair Grove. He currently grows Bibb lettuce in his raft hydroponic

system he built by hand. His small lettuce farm has doubled after

less than three years of production with the second, identical solar

passive greenhouse built recently. These two greenhouses combined

produce 1,400 pounds of Bibb lettuce per week. Young sells the

best heads of lettuce to local restaurants and grocery stores like Hy-

Vee. He sells the smaller, imperfect lettuce heads to the Springfield

YMCA after-school program. His lettuce has quickly become the

popular choice for Springfield citizens who enjoy the benefits and

taste of his local, sustainably-grown lettuce.

Young sees the future of his farm growing by one or two more

greenhouses, and possibly experimenting with different varieties of

lettuce grown hydroponically.

About the greenhouse

The Young Family Farm has two solar passive greenhouses. These greenhouses differ from traditional

ones due to their unique construction design.

The solar passive greenhouse has three sides of metal, with the south facing side being plastic. The green-

house is heated by the black barrels of water being heated from the sun. These greenhouses aren’t very

common, however they are extremely efficient and low cost to maintain. The only electricity needed for

the greenhouse is to run the fan. Where the size of a conventional greenhouse will need two fans, this

greenhouse only needs one to stay as cool. It is important to use a very thin screen to cover the vents in the

greenhouse so you don’t blow in insects such as aphids and thrips.

Starting small

Young has experimented with the best way to start his

seeds until he found a system he liked best. To keep things

consistent, Young starts his seeds in oasis cubes and places

them under lights for the standard 8-10 hours per day. The

reservoir that feeds his seedlings has a small aquarium

bubbler he bought for cheap from a pet store.

This solar-passive greenhouse is heated from the barrels of water, pictured right

Jesse starts his seeds under lights

Company

Profile

Saskatoon, Canada is

where Ecobain Gardens

produces and sells their

colorful microgreens.

Ran by a husband and

wife team, they are liv-

ing every gardener’s

dream of having almost

complete control on

how they grow their

food. Ecobain Gardens

is extremely sustainable

due to their zero-waste

approach and media-

less growing method.

NFT micro greens in Saskatoon, Canada

Ecobain Gardens Ecobain Gardens is another great success story of a family-

owned hydroponic farm. Founded by Brian and Roberta Bain,

this small operation has impacted their Canadian city by growing

microgreens in a sustainable way.

The microgreens are grown in an environment-controlled facility

that ensures even, predictable growth. The temperature is always

right, the light is always adequate, and production is always

steady. The microgreens are grown vertically in an NFT system,

which allows them to grow more food per square foot. They have

control on just about every single factor of growth. They also use

no pesticides, a major benefit of indoor urban gardening.

Ecobain Gardens microgreens can be found in local Saskatoon

organic and health food stores, as well as at farmer’s markets.

With taste testing and practical, beautifully designed packaging,

they are quickly making a lasting impact on their local communi-

ty and their cuisine.

What are microgreens?

The growth stage between a shoot and a baby green is considered a microgreen. Plants are harvested slightly

before or slightly after the first true leaf emerges. Not only are microgreens a popular alternative to lettuce due

to the unique, flavor-packed taste, they are also at least four, and up to 40 times more nutritious than when

they’re mature. This is thought to be because the seedling is getting ready to grow very big, and therefore has a

lot of nutrients stored up to do so. Microgreens are more than just a garnish, they can be used as a substitute for

lettuce on sandwiches or tacos, as a lettuce by itself, or even in smoothies. The options for using microgreens in

dishes is as endless as it is nutritious. Some seed companies, such as Johnny’s Selected Seeds, make specialty

microgreen salad mixes based on compatible flavors. Some common vegetables used for microgreens include:

kale, radish, mustard, mizuna, arugula, cilantro, beet, cress, and

kohlrabi.

No media is the best media

One of the most unique aspects of Ecobain Gardens is their zero-

waste approach to their sustainable growing. They don’t use any

growing media, which allows the leftover roots, shoots and seeds to

be fed to local livestock. The roots are very nutritious for the cows,

pigs, and goats who consume them, and it helps Ecobain Gardens

connect to the community even more. They go through a process of

soaking the seeds for two days, then sowing them carefully after the

radical emerges. Once the roots start to develop their “mat” they are

transferred to the NFT hydroponic system.

A blend of radish microgreens

A close up of the microgreen’s roots

An Ecobain mix salad of microgreens

Photo references

B. Bain, Ecobain Gardens

E. Couture, Lil Em’s Gar-

den

J. Young, Young Family

Farm

Nourishtheplanet.com

T.A. Produce, tapro-

duce.com

Sdhydroponics.com

References (B. Bain, personal communication, May 1, 2015).

Brechner, Dr. Melissa, & Dr. A.J. Both. (n.d.). Hydroponic lettuce

handbook: Cornell controlled environment agriculture.

Helweg, Rick. (2014). How to grow fruits, vegetables & house-

plants without soil: The secrets of hydroponic gardening

revealed. Florida: Atlantic Publishing.

(Hydroponic Micro Farms, personal communication, April 25,

2015).

(J. Young, personal communication, March 22, 2015).

Lil Em’s Garden: Growing food and ideas