Biological Pest Control – Lesson 11


Pesticides are not the only way to deal with
pests in our gardens. Nature also gives us the answer to pests. Typically, we call them
“predator insects.” There’s a variety of pests you could experience
in your garden. For example, spider mites and the predator for spider mites is called
persimilis. It’s a predatory mite that eats something like 12 spider mite eggs a day and
up to 15 spider mite adults a day. They can be effective. There’s a few things to know
about using persimilis in order to have good success, that is, the environments between
the two pests are opposite. Spider mites like it hot and dry and that increases their reproductive
rate. Persimilis likes it cooler and moist. It’s definitely to our advantage right away
when we get spider mites, we drop our temp, raise our humidity. That slows down reproductive
rate, drop the temp to 80 degrees Fahrenheit, raise humidity to 60 percent, and then at
that point, if we can maintain those environmental conditions, we could be considered a viable
candidate for predators because we have to have that environment. Otherwise, if we put
the predator in the garden and it’s too dry and too hot, then the predators are just
going to die off and the spider mites are going to take over in which case it will be
a waste of money and the client could be left with a poor impression of predators. But predators
can work very well. As long as we establish the correct environment,
then we can have good success, but keep in mind when we’re using predators, it’s
really a commitment. It’s not going to be a contact kill like a pesticide where you
just put them in there once and your problems are solved. What greenhouses and major crop growers do
is they do leaf counts. Essentially, they take a leaf. They count the number of pests,
they count the number of predators, and they have the ratio that they consider to be a
natural balance. In some scenarios, these greenhouses, they never get rid of their pests.
They keep introducing predators and keep the pests under control, creating an environment
that allows them to get big yields because keep in mind, in general, pesticides reduce
yields. It’s not nature’s way to just make something
go extinct. Nature creates balance, so that’s where the predators come in. It is possible
at times to actually eliminate infestations with predators. It definitely can be a financial
commitment and once you go down that road, you can no longer apply pesticides in your
garden, so it is good to fully consider these matters. There are other pests like thrips
for instance that there are predators as well. We use cucumeris, which is a predatory mite
that feeds on the thrip nymph existing at the root zone level. There is [unintelligible
0:03:22] a predatory wasp, which feeds on the thrip adult and this can be quite effective
because thrips can be very difficult to eliminate. Sometimes a thrip infestation can go on for
more than a year and sometimes predators are the only way to get rid of thrips. There are a number of other pests that we
have predator solutions for like fungus gnats. There are predatory nematodes available that
we can apply to our root zone, which will attack the fungus gnat larvae very aggressively
and eliminate them quite thoroughly. Hypoaspis is a predator for fungus gnat adults and these
solutions can be viable. Definitely talk to your local hydroponics
store about predators. You can be a part of reducing pesticide use in the world and creating
a natural biological balance in your grow room.

2 thoughts on “Biological Pest Control – Lesson 11

  1. been using essential oils to totally eliminate mites of all kinds especially red mites.
    clove oil
    rosemary oil
    lemon and eucalytpus mix oil
    peppermint oil
    citronella oil
    neem oil
    and Dr bronners soap

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