June 2021 - 28

PRODUCTION
Roots, Shoots &
ENVIRONMENTALS
This first in a series of three articles about optimizing your
greenhouse focuses on ways growers can increase productivity
and efficiency through their growing medium.
BY CARL SILVERBERG
A
s an experienced greenhouse grower in
New Jersey once told me, " Optimizing
your greenhouse potential is all about
understanding your root zone to your shoot zone
and the environmental impacts that affect both
of them. Optimizing also means sustainability
of not just your processes, but where your
resources are coming from. "
Is the goal of optimizing to find the one
perfect way to do things or is optimization more
of a personal preference? Most growers would
say that there are several ways to optimize and
there is no single " best way. " They would also
agree that by the time you see the effects of
problems in the root zone, you're already behind
the eight ball. That's what we're going to focus
on in the rest of the article.
SAP ANALYSIS
David Miller is with Advancing Eco Agriculture,
a company that specializes in finding problems
as soon as they occur. " A lot of what happens
below the surface is affected by what's in
the leaf, within the plant. The plant feeds the
bacteria and in return, the bacteria and the fungi
agree to make nutrients available to the plants.
If you have a nutrient deficiency or excess, the
plant will photosynthesize less efficiently. The
decline cycle continues because you no longer
have that symbiosis going on. "
His company uses an interesting technique of
sap analysis for nutrients (see Figure 1). As an
example, by the time you see visual verification
of a problem in tomatoes such as leaves turning
yellow, the plant is already cannibalizing itself
to try and keep growing. " The heart of what we
do is grow food as medicine, " Miller says. " The
medicinal compounds are really what bring out
all that flavor and aroma of what we know as
good food. It's all based on the mineral balance. "
ROOT COATING
Sap analysis will help determine whether or
not you have a problem, but can you prevent
problems in the root zone? We posed that
question to Michael Brownbridge of BioWorks.
" If
your
root
system
isn't
functioning
properly, your plant won't
grow as well, it won't mature as quickly or it
will simply die. And, that's irrespective of the
way you're growing it, peat-based, substrates
or hydroponic systems. A healthy root system is
fundamental to a healthy plant. "
That gets back to what Theodore Huggins,
iUNU's senior horticulturist, reminded me. " In
a root zone, you can optimize your greenhouse
by inoculating your plants against fungus and
controlling pests before they become a problem.
From the root zone, you can maximize your
fertilizer inputs. "
Brownbridge explains that his company
focuses on putting beneficial microbes into the
soil where they coat the root surface and they
grow with the roots to prevent root diseases.
The microbes improve a plant's capacity to
utilize fertilizer more efficiently (see Figure 2).
" Organisms help roots develop, to colonize
growing substrate more effectively, and they
do it by promoting root hair development. This
helps a plant absorb nutrients more efficiently,
solubilize, and move some of the critical
elements of the media. "
He was careful to point out that supplements
Figure 1. How sap analysis tracks the plant cycle.
(Photo: David Miller)
28 JUNE 2021 GPNMAG.COM
Figure 2. The result of beneficial microbes in the
soil. (Photo: Michael Brownbridge)
are not a replacement for fertilizer; they're
organisms that help plant roots develop by
promoting root hair development. Plants absorb
more efficiently, thus their overall nutrition plan
functions more efficiently.
http://www.GPNMAG.COM
June 2021

Table of Contents for the Digital Edition of June 2021
