Selecting a Growing
Structure for Fodder Production
By Maxwell Salinger
One of the common
questions often heard at CropKing is the optimal environment for
hydroponic fodder production. To begin to address this topic, one of
the first catch phrases that come to mind is “controlled
germination.” This term fits well with hydroponic fodder production
because we are only concerned with the first seven to fourteen days
of growth. These plants are relying very little on the sun to provide
the energy they need to develop, and more on their “food” stores
within the seed. This “food” or endosperm inside of the seed is
most often in the form of starch. Starch can be
converted to a more
easily digested form for our livestock to consume through the process
of germination. These facts alone can certainly influence the way we
approach our environmental control.
Like any other crop, the grain seeds
we use in a hydroponic fodder system germinate best in high humidity
environments. In vegetable crops we often use a humidity dome or a
propagation greenhouse for the first couple of days before emergence
to keep our relative humidity at 90% or above. This is where our
fodder starts to stray from normal germination conditions. Although
having humidity levels close to this 90% range may speed up
germination, it also speeds up the growth of many molds that can be
extremely detrimental to production as well as animal health. It is
for this reason we look for a humidity range that encourages
germination to a satisfactory rate but does not aid in the
proliferation of these molds. Having precise control of these
humidity levels is thus of paramount importance.
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| CropKing's research fodder building |
Having solid control of this humidity
can be more challenging task in some buildings more than others. Here
at CropKing I am fortunate to have a 30’x40’ steel structure that
is heavily insulated with a spray foam material with a high R-Value.
This means that my heat and humidity are well conserved and it is
generally not difficult to keep my relative humidity above the
minimum of 60%. It is rare for the relative humidity to drop to a
level unacceptable for germination when at least one of my fodder
units is up and running. Dehumidification though can definitely
become a necessity. There are many equipment options when looking
into dehumidification such as “heat pumps” to the more cost
effective “at-home” dehumidifier made for keeping your basement
less muggy. Heaters can also go a long way to reducing ambient
humidity, but regardless of how you do it; the humidity must be kept
below 80%.
If these facts are kept in mind while
deciding where to put your fodder rack some basic questions arise;
Such as, how much will it cost me to heat/ cool this structure and
what will my dehumidification needs be? When answering these
questions it becomes apparent that it is much more cost effective to
run this type of system in an enclosed and heavily insulated
structure such as my steel building. It seems that it is becoming
more common for people to start growing in
structures such as
greenhouses or poly-huts. The main benefit to growing anything in a
greenhouse structure is the accumulation of “free” sun energy,
which as stated before is not the main concern  |
| CropKing's research greenhouse |
facility.
The results were fairly surprising,
the average wet weight and overall height of both sets were almost
identical in both replications. Where I saw the biggest differences
was in the actual grass morphology. The greenhouse grown set
allocated more energy toward the production of roots than shoots,
opposite from that of the fodder building group. These greenhouse
shoots were shorter but the blades were wider and more expanded,
implying that they were actively photosynthesizing at a higher rate
than the closed blades of the fodder building’s shoots. These
results led to the question of protein and fat allocation; “Is it
better nutritionally to have more shoots or roots?”
After getting
samples of both groups sent to Clemson University to be analyzed it
became apparent that much more of the protein and fat within the
plant is stored at the shoots of the fodder than the roots. Of these
shoot samples within this study, on a 100% dry-matter basis it was
also shown that the fodder grown in the enclosed structure had a
higher protein content of 21.9% verse the 17.6% of the greenhouse.
Similar results could also be seen in the comparison of the two sets
of root samples.
While comparing these two growing
environment systems it seems as though in reference to production and
economics it is more advantageous to grow hydroponic fodder sprouts
in an enclosed and more controlled environment. This is not to say
that greenhouse production is out of the question, especially if
hydroponic fodder is the sole crop being grown. Like any protected
agriculture crop, the benefits of hydroponic fodder must be weighed
against the cost of the operation of the equipment as well as the
cost of environmental control.
