What are nematodes?

And what are they used for?

Nematodes are basically primitive non-segmented worms, and are actually the most abundant multicellular animal life-form on the entire planet, making up 80% of all the animals on earth. And about 50% or more of them are parasites of insects, plants or animals.

They are most often microscopic or nearly so, and a half cup or less of average soil will be inhabited by thousands of them.

They are among the multitude of other microbial unicellular, multicellular and invertebrate organisms that can be beneficial or pathogenic like the other microbes that will be in your soil, like the beneficial or harmful bacteria and/or fungi that will also be found in all soil.

Happy growing,


1 Like

Okay, thanks… I guess what I’m asking is the guy at the gro-store said they will kill the little black flies in my soil, is that so?

How else will they benefit my soil?

Also he said the little package would make 5 gallons and to just water normally with it, is that right?

After I mix it how soon do I need to use it?
(I’m thinking they probably can’t swim for long lol) so mix it up and use it right away, right?

Honestly I didn’t read the package yet, I come here for my info, thanks Mac G

Yes, if you get the right ones they are parasites that would kill the larva of the fungus gnats in your soil.

There are different microbe additives with different beneficial microbes, I’m sure directions will vary, I’d follow the directions that came with this product.

I’d imagine what ever batch you did make up should be used fairly soon. I’m not sure they’ll drown per se, but the mix alone wouldn’t likely have much of what they need to survive for very long, get them in the soil quickly so they can do what they do.



“Beneficial nematodes only attack soil dwelling insects and leave plants alone. The nematodes enter the host through body openings or by penetration of the body wall. Once inside, they release a bacterium which kills the host within 48 hours. The nematodes continues to reproduce and its offspring begin to seek out new host material. Beneficial nematodes are a totally safe biological control parasitic insect organism. The Beneficial nematodes are so safe the EPA has waived the registration requirements for application.”

Put the contents of nematodes in a bucket of water and stir to break up any lumps, and let the entire solution soak for a few minutes. Use immediately, mix continuously to prevent settling.

1 Like

I’m using ffof soil, aren’t there already beneficial nematodes in it?


Yes, there are probably tons of them, they are pretty much everywhere, not unlike bacteria and fungi, pretty much everywhere.

However there will be the natural proportion of good and bad nematodes, and a significant amount of them that wouldn’t necessarily be all that beneficial nor harmful.

Think of it kind of like a garden where you have a mite or thrip problem. Sure you might have a ladybug or two flying around in the garden hunting and eating a few here or there, but not enough ladybugs to get rid of the infestation from your garden, so you buy a box of a ton of ladybugs and let them run loose in your garden.

Now you have enough to wipe out and overwhelm the bad bugs in your garden, eliminating the problem. Sure when the ladybug’s food – the bad mites and thrips is gone, they will move on or die of starvation, but by them you won’t care cuz the bad stuff has been destroyed.



…so I tried the nematodes, I haven’t had one gnat come back yet!

I used nematodes and yellow sticky strips & it did the trick for me! Thanks MacG!


Nematodes during flower ok? :thinking: