A Birdseye View into the Different Types of Hydroponic
Growing Systems
Hydroponic gardening is the way of the future for
environmentally controlled agriculture.
Hydroponic gardening eliminates soil borne pests and diseases and
maximizes water and nutrient uptake by the plant. Incredible yields can be achieved in a
relatively small space with hydroponic systems.
There are many types of hydroponic systems available for home and commercial
use. These systems include the Europonic
Rockwood System, the Ebb and Flow System, Aeroponic Systems, Continuous Drip
Systems, and Rockwool Based Systems. Hydroponic systems come in all shapes and
sizes and can be adapted for nearly any budget.
Nutrient Film Technique, or NFT, is another popular
system. The plants are held in troughs
with nutrient solution constantly trickling over the roots. A reservoir with a pump that is submersible
re-circulates the nutrient solution continually, pumping the solution to the
top of the troughs to trickle back through the system. Larger Nutrient Film Technique systems are
used commercially, both abroad and in the United States. When choosing a Nutrient Film Technique
system, care must be taken to choose the correct trough size. Large commercial systems use wider troughs
with greater flow capacity. Aeroponics
is a system in which the plant's roots are suspended in air. They are excellent for growing herbs and
leafy vegetables. The plants are held in
web pots with neoprene inserts to support the plant. Different hold configurations in the top
cover provide the proper spacing.
Aeroponic systems are also great propagators. The seedlings can be germinated in Rockwool
then transferred directly to the web pots.
Aeroponic systems are also very popular at NASA research centers and other
educational facilities around the world.
The Europonic System is modeled after commercial systems
that are used in Europe. A basic system has three trays and holds
eight plants each. The system may also
be expanded to five trays if desired. A
nutrient solution is pumped from a thirty-gallon reservoir to individual
emitters at each plant. The solution
trickles through the Rockwool, over the roots, and back to the reservoir where
it is re-circulated on a constant basis.
Rockwool, or mineral wool, is the most popular and highly used
hydroponic medium. It is made from spun
material fibers and has a high water and air holding capacity. It can also be cut and formed into many
shapes and sizes that allow many diverse growing applications. The Europonic System uses Rockwool slabs with
two slabs fitting into each tray.
Rockwool is easily able to support a relatively extensive root system so
the Europonic System is ideal for vine crops such as tomatoes, cucumber, and
peppers, plus large flowering plants.
In a continuous drip system, a single pot is used with a
two-gallon reservoir underneath. The
system acts like a percolator as air is pumped down a vertical shaft, creating
pressure, and nutrient solution is forced up another tube. A drip ring constantly irrigates the
substrate, and the nutrient solution drains back into the reservoir. This type of system is easy to use,
inexpensive, and great for individual experimentation. However, it is impractical for most
commercial applications. Ebb and flow systems
are also popular in hydroponics. They
are good for crops such as lettuce, pepper plants, miniature tomatoes, and
potted flowers. Ebb and flow systems can
also be used as an herb garden to provide fresh basis, thyme, and oregano year
round. Ebb and flow systems do have a
few drawbacks, one including the possible buildup of fertilizer salts in the
substrate. As the water evaporates
between flooding, the salts are left behind as a residue and may rise to toxic
levels. It is best to flush the system
with pure water periodically to take away any toxic salt buildup.
