June 2024 - 25

PEST & DISEASE MANAGEMENT
benches and sidewalks, sweep up the
excess media, get leaf tissue picked
up and then, typically, you treat the
surface with those products.
I can't endorse any one particular
product, but the products are useful.
The key is the wetting time. For
instance, with a lot of the quaternary
ammonium products and many of the
other products, they require at least
10-15 minutes of wet time in order to
kill the pathogens.
Follow the directions on the label.
You want to avoid sanitizing during
the heat of the day. Early morning
or later in the day is best, when the
product can stay wet for that period
of time.
When you say underneath the
benches, what specifically are you
talking about?
NR: Well it depends on what
is underneath the benches. If
you have a ground cloth or
Root rot can cause big losses
so sanitizing between crops
will prevent further spread.
It's really important to scout
the plants - monitor them on a
regular basis - so that you can
catch problems early before they
develop into bigger problems.
cement, it's easier to clean up organic
debris after the previous crop. It's also
easier to sanitize because there's no
place for pests to harbor. If you have a
greenhouse where there's native soil or
gravel under the benches, sometimes
it's difficult to remove the media that's
fallen down below the bench.
You can still treat under the bench,
but it's a little bit more challenging
because you can't totally remove the
organic material.
Once you have your greenhouse
sanitized and you bring everything
in to keep it pest and disease free,
do you have any tips for maintaining
the cleanliness?
NR: When you start clean, it's
easier to stay clean because you're
starting with a greenhouse that
doesn't have any insect pressure;
it's easier to maintain.
There are products that you can
use during production for control of
fungus gnats and shore flies. Citation
insecticide controls both pests and
you can generally apply it, usually in
propagation where the pests tend to
be more of an issue early on. You're
maintaining those conditions; that
you can stay clean with those types
of applications.
There are different predatory mites,
Look for botrytis infections in the lower
canopy of calibrachoa.
like Hypoaspis miles, that you can
release underneath the benches.
Like those benches that have gravel,
where maybe it's difficult to get
treatments on the floor, this can help
maintain or reduce the populations of
those pests under benches.
You're going to make preventive
applications to keep these pest
problems from developing in the
greenhouse. And generally, if you
start clean, it doesn't require as many
preventive applications to keep them
out because you're keeping pressure
to a low, manageable level with your
applications, making sure that some
plants are protected and they don't
develop any issues.
As a grower, you still need to have
a good pest management program to
stay clean, do you agree?
NR: Yes, you do, and you have to
have scouting. It's really important to
scout the plants - monitor them on a
regular basis - so that you can catch
problems early before they develop
into bigger problems. That way you
can provide the solutions for treating
them before it's too damaging to
the crop.
Is there anything else on
greenhouse sanitation you think is
important to share?
NR: I will add that it's really
important to clean up the production
area in between your crop cycles.
When you're done shipping one
crop out, make sure you go in and
clean up those areas. It really does
help prevent other problems from
developing in the new crops that you
introduce to that area.
GREENHOUSE PRODUCT NEWS 25
June 2024

Table of Contents for the Digital Edition of June 2024
