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Picking the Best System to Grow
By: Tim Walker
Courtesy of
Maximum
Yield Magazine
Let me say before I get into too many details that growing is
like any other pursuit. There are simple ways to grow and more
complex ways to grow. The best is not always the most
complicated and conversely the easiest is not always the
simplest (or cheapest).
For most people, a simple method that is easy to maintain and
not overly complicated is probably the best. Also, the most
forgiving method might prove to be the best way to grow
because there are fewer things that can go wrong. Choosing the
best system may depend on how much time you want to devote to
this venture. The problem with good old-fashioned soil (dirt)
is that often it is not sterilized and contains pathogens,
weed seeds or it may be highly lacking in nutrients. During
this discussion we will be talking about “soil-less” methods,
which means using a pre packaged growing mix such as Sunshine™
or ProMix™ or a clean, sterilized, inert medium. A medium
could be any one of many suitable products and may include;
clean sand, pumice, vermiculite, perlite, clay, sawdust etc.
All have been used to some degree of success and can be
considered an artificial medium. A “soil-less” medium usually
means a peat moss type mixture.
Should I use an NFT system, an Aeroponic system or just grow
in soil? The answers again will lie in what you hope to
achieve. If you are growing for profit or for maximum
production then you may want to consider a faster method. If
higher yields are what you had in mind, then maybe a different
method is the best choice. Let’s explore all the common
methods and see which is best for you.
Hydroponics in it’s truest form (not how the papers easily use
this term) is a method where plants are grown in an artificial
medium ranging from peat moss, sawdust, sand, gravel, rockwool.
perlite etc. and are fed a strict diet of nutrient-rich water
on a constant basis, so that they are never lacking in any
mineral or nutrient for the entire life of the crop. Most all
of these systems are great if you are an expert on nutrition
and on monitoring the nutritional levels and have a good
working pump system and plan to be there 24-7. If you leave or
the power goes off and the pump shuts down then you have a
problem. Believe it when the power for the lights or the water
pump shut down for any length of time you will remember the
term “Houston we have a problem!” Most people simply do not
have the time or expertise to devote to true hydroponics
growing.
Why then do people choose hydroponics or similar versions of
this system? Simply because the yields can be much greater
than traditional garden yields. A study once showed that an
acre of field tomatoes could produce on average x number of
kilograms or lbs per acre per year. Growing in a greenhouse
for 11 months of the year using hydroponic methods under ideal
conditions, demonstrated that the yield difference could be as
much as 11 times (11x kg/lb per acre) greater than in the
field. For one thing, the field crop could only produce a
single crop per year in a moderate climate, whereas the indoor
garden could produce two to three times per year depending on
the cycle. On the other hand the outdoor crop was not
monitored as closely and the amount of fertilizer
applications, pruning, and general maintenance was much less.
Growing outdoors the danger was being at the mercy of the
weather, be it ideal condition or horrible conditions. The
trick is achieving the best of both worlds and choosing the
correct methods can do it. Growing indoors under ideal climate
conditions but using modern growing methods is ultimately the
best route to take.
Let’s look at some of the techniques or cultural options open
to growers.
The NFT System
A good example is
the
The Progressive Growth High Flow Growmaster
The NFT or Nutrient Film Technique is a system where the roots
of the plants are held in a trough or plastic film and a
continuous light river of water runs over the roots
constantly. The water is then recirculated back into a main
reservoir or tank and then sent out to the same plants over
and over. The advantages are increased aeration that supplies
plenty of oxygen as well as nutrition. Every couple of days
the water is tested and remixed with the correct ratio of
nutrients added to the tank and the water topped up again.
There have been several modified and updated versions of this,
such as the hydro canal system, and NFT is still used to some
degree today, mostly in the UK.
Capillary Matting System
A good example is
the
The Progressive Growth
Ebb N Flowmaster
This system uses a similar technique where the plant roots are
grown on large fiber mats made of a water wicking substance.
The problem with these was that often the roots only fed at
the bottom level or the materials, were too porous, encouraged
algae growth and were usually expensive. Not many crops are
produced today except where bottom feeding (i.e. African
violets for example) is needed.
Aeroponics
A good example
is the
The
Pipe Dreams
Aeroponic Systems
Aeroponics is growing in a 4-6” PVC pipe or tube with holes
cut in it for the plants to sit in. Usually a small mesh
basket is placed in the hole with the roots sitting in the
basket filled with clay pellets or coir (coconut fiber).
Inside the pipe a small micro jet mister, something like you
see spraying in the produce section of the store, is used.
This mister supplies a high level of oxygen plus nutrition to
the roots of the plants. The water then runs down the pipe
that is usually slanted a few degrees toward the main pipe or
return tank. The water is then remixed and returned out under
pressure to again be mist fed at the root zone of the plants
This method was popular in the 1990s and saw some remarkable
growth, incredible root systems and often an increase in the
crop cycle time. Peppers, basil and other crops produced in
record time with remarkable growth. Unfortunately the
drawbacks were the reduced size of the plant you can produce
and possible algae growth. Another drawback is in the event of
power loss or if the pump shuts down you have a very short
time span in which to repair it or find alternate power before
you begin to loose your entire crop.
Bucket System
A good example is the
The Progressive Growth Power Buckets
Essentially the bucket system uses five gal (20 litre) black
or white plastic buckets with a hole cut in the lid to support
a three to four inch plastic pot or mesh (net) pot filled with
clay or gravel. The plant goes into the mesh pot that sits ¾
of the way below the lid and the roots drop through the media
and search for the nutrient rich water, which is circulating
in the lower portion of the bucket. A 5/8”-3/4” inch thru-hull
marine type fitting goes on the bottom of each bucket. In one
central bucket or tank (often made using a Rubbermaid™ type
plastic container) is the reservoir tank that holds the return
nutrient water. A small pump is used to send the nutrient
“back out” to the buckets through PVC pipe and fed into each
pot by black spaghetti tubing. The incoming and freshly
oxygenated water is dripped on to the top of the mesh pots
providing new water, nutrient and oxygen for the plants. These
systems can be constructed easily at home and usually have
6-10 bucket sites per pod. Each pod is usually set out in a
star or circle formation and the thru hulls are connected with
rubber watering hose of the same size 5/8” or ¾”that returns
the water back to the main reservoir. Bucket systems work well
but again the drawback is forgiveness. If the water and
nutrient are changed regularly and the pump is never shut off
plants will grow at an accelerated speed, but if the power
ever shuts down or the pump goes you can be in trouble in a
short amount of time.
Chamber or Wheel system
One of the best examples of this is on display at the Epcot
Center at Disney World in Orlando, Florida. Although these
systems achieve speedy growth and unbelievable root systems
they are by all accounts not very practical and high in
maintenance. These systems are designed to provide extremely
high light (phototropic periods) and increase the plants
ability to grow and mature at an accelerated speed in a
high-density area. Again the positive is high-speed growth
potential and the negative is the unforgiving factor should
something go astray or the power shut down.
Flood Tables
The flood table system uses a plastic table with raised sides
capable of handling about 2 ½” of water and uses an ebb and
flood type practice. Ebb and Flood system is essentially a
fill the tub and drain the tub concept all done in a matter of
minutes. Usually plants are grown in stone wool (rockwool)
blocks or in small mesh or net pots. The pots are filled with
a media that will not stay saturated for long, but allow the
roots to wick up nutrient water, dry out again very quickly
and yet allow for good oxygenation. Usually a timer is set to
turn on the pump and the bench “floods” for a time period that
raises the water level up to about 1/3 to 1/2 the level of the
pot or block. After this flood period the timer shuts the pump
off and the filling subsides and the water begins to drain
back into the tank or reservoir. By allowing for a dry out
period of several hours the roots can uptake the necessary
nutrients and still not drown. The lighting would be on to
coincide with the time period of the ebb and flood.
Container Gardening
Container gardening is where plants are grown in a container
made from either plastic, ceramic clay or fiber. The
containers usually are a round pot, pail or a plastic growing
bag shaped on the bottom like a paper bag. The chosen
container is then filled with a sterilized and artificial
mixture. These mixes are predominantly made from peat moss
with the addition of perlite, pumice, vermiculite, sand,
sawdust or other amendment.
Some mixes contain added wetting agents or moisture holding
agents and some contain a charge of nutrient to initiate good
plant growth. Other mixtures may include coir (coconut fiber)
or loose rockwool instead of peat moss. The size of the
container will often dictate the size of the plant growth
desired.
The idea is to plant the plants in these containers in a
controlled environment with nutrient being added either by
means of an automatic drip or sprinkling system or by hand
watering. The disadvantage is sometimes the growth is less
accelerated than with some of the high tech methods and hand
watering is laborious. Also, hauling in and out large bags of
“dirt” is cumbersome, but often the old or used dirt can be
spread on the outdoor garden or lawn as a great addition to
the garden. The big plus to container gardening is that it is
so much more forgiving than many of the other methods.
First of all an organic-based material, such as dirt, often
assimilates organic matter more easily than in a water culture
method. Secondly, if a day of watering is missed or a pump
shuts down the plant will usually have residual moisture left
over from the last watering session.
Controlled Environments vs. Uncontrolled
One has to think why we have indoor farmers that produce high
tech crops such as our hothouse peppers or tomatoes and why we
have field grown crops such as tree fruits, cereal grains and
field vegetables. The rationale is simple economics. A lot
more can be produced outside at a slower, less controlled rate
cheaply and a lot higher quality fruit can be produced in a
high density controlled indoor environment. The difference is
cost, time and error. If the indoor farmer forgets to water,
it is a catastrophe, whereas the outdoor farmer often just
hopes for rain on an un-irrigated field. For a grape grower
producing a field crop but using a drip irrigation system, it
is sort of the optimum of both worlds. He cannot control the
weather, but he can work in harmony with it only adding water
and nutrient when he sees the need. Both of these types of
growers can also choose to produce organically as well, if
they so choose.
As in all systems, learning the little subtle tricks of
growing in any particular culture is important. All of these
systems mentioned have been used to a high degree of success.
The most difficult part is creating a system that works well
and is both low maintenance and forgiving. The more recent
trend has been to go back to container growing with an
artificial soil less mix type medium or an organic mix. Either
hand watering or automated irrigation is usually the chosen
method, with automated being the more prudent from a time and
labor point of view. When deciding which system works best
speak with your sales rep or store manager and weigh the
options and choices against what you want to accomplish. If
you’re serious and passionate about this, then maybe a more
complex method will be fine. If you are looking for a more
relaxed and simple system, then another may be right for you,
Accessories
As with any growing method you must supply ample air supply
and circulation by using good quality fans and placing them
properly. You must also provide optimum light, whether using
artificial HID lighting systems indoors or providing natural
light in a greenhouse or cold frame. Using a high quality
nutrient and mixing it with clean PH neutral water is also
critical. If you’re not on regular city type potable
(drinkable) water then you need to look at your water source
and have your water tested. The best system in the word will
not work properly if your fertilizer is poor or your water is
bad. Choosing high quality fans, lights and fertilizers will
complete the circle of success. Don’t use this as a place to
cut corners and” save” money. Once again ask your trusted
storeowner or sales rep for the best systems available.
Creating a System
There are many excellent books on building your own indoor
greenhouse or hydroponics system and a large number of web
sites that also provide great information. Books by people
like Howard Resh, a noted authority, entitled Hydroponics
Questions & Answers and published by Woodbridge Press of Santa
Barbara or the Best of Maximum Yield available from the
publisher of this magazine could be a great help. Also I am
sure Mr. Erik Biksa of the “Ask Erik” column would be happy to
lend some advice and answers to your questions.
Some excellent web sites that you may want to look up as well
include:
www.wisegeek.com/what-are-indoor-hydroponicsystems.html
www.howtohydroponics.com
www.acs.edu.au/outlines/advhydro.asp
There are many companies that advertise in this publication
(Maximum Yield ™ magazine or Industry News™) with an extensive
offering of system types, options, prices and components for
the do-it yourself person. Check the web sites and catalogs or
contact your preferred suppliers for the choices available and
ask what the benefits vs. features are. Growing, like any
other business or hobby, offers many options. Doing your
homework first will pay off greatly later on. Good Luck!
Tim Walker is a businessman and consultant with 26 years of
industry experience in horticulture, sales & marketing. He
resides in the Okanagan Valley of British Columbia.
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