Problem with RO and fungus gnats?

Anyone had a problem with Roots Organic Orginal being infested with fungus gnats? Switched from Dr Earth to RO last grow and had an infestation of gnats, didn't really see any adverse effects, just annoying. Bought 2 more bags for my current grow and just started seeing the same problem. Is this common? I've tried a hydrogen peroxide solution to rid the soil and it's done nothing so I guess I'll ride it out again. Will definitely not be using this product again which sucks because I had heard rave reviews about the composition.

Yes very common. Let the top layer of soil dry out & sprinkle on a layer of diatomaceous earth. If there's a lot of them get sticky traps to catch the flying fuckers. They be gone in a week & if you keep fresh DE on top they won't be back. Add some neem seed meal to your mix and cook it in if you recycle your soil after harvesting. Works well against a slew of gnats & other creepy crawlers like thrips. Gets in the flesh of the plant & wards off leaf munchers.
Gnats can only survive in containers if you leave your soil too wet for too long. They come in with healthy bagged soils of every brand. A few insects are par for the course in organic soil so prevention is the key. Roots organic is good stuff don't let a few bugs ruin your opinion. If you use smartpots you can put a tray underneath and water from the bottom which will make it very uncomfortable for gnasties. Cover your soil with a paper plate or mulch it to keep the fuckers from laying more eggs. The DE will tear them to shreds if they try to land; put it on heavy. It actually is a good source of silica too once it breaks down.

I ordered some nematodes on amazon. If they don't work I will try DE. I do use smart pots so maybe watering from the bottom is the answer. Thanks though.

SF nematodes works well for me

I had gnats about a week ago, ordered nematodes from Amazon, took forever to get here, but there was a huge difference in a day. Now I swear by them

How many nematodes should I use? I ordered the 5 million per whatever. I assume there's instructions on the back for how much to use for 5 gal pots?

Just get some mosquito dunks crush them up, put them in your water let it soak, use it to water and done... Or powder, put on top of your soil and water in. All organic. Also when breaking it up, put it a bag or two to crush, don't breathe it, don't lick it, or your hands... It's bacteria that eats gnats from the inside out...

Mine came in packets of folded sponges. I soaked the sponge (it will have some muddy puddy with the nematodes stuck to it) in a 16oz cup until the mud was all suspended and then watered with that.

My garden is small, so I might have went overboard with application, but literally the next morning I saw various stages of gnat heading to the surface in what looked like panic.

I ordered 10M, they came in two sponges, I used one sponge about a week out from the other. My feelings are that the plants responded well to them so I will probably keep using them as a preventative once every two months or so.

**I tried mosquito dunks (crushed and microbe lift BTi) tanglefoot, dishes of sweet coffee, peppermint tea, dead-bug, gnatnix. None of this worked over a period of 6 months or so. Only the nematodes worked, and worked overnight.

I run amended recycled soil. One of the things I put in the amendments is crushed dunks. I also have a plastic ice cream bucket with water and a dunk floating in it, the lid has holes drilled in it so if the flyers want a drink...

And I run yellow sticky traps by the lights or yellow duct tape strips on the cheap. I also cut up or find, make the small yellow traps and put them in the pot.

It's parts of my screw them first way of doing it... I add new soil when I recycle so I see a few for a day or two then gone...

Edit: forgot to add I also use crab/shellfish meal which has chisin or how ever you spell that, bugs hate it. Also helps plants to get a sar response or high brix. I'm Stoned and can't remember...

Bugs do not hate chitin they are made of it lmao... The reason it's helpful is there are microbes of some sort that feed on chitin so boosting those populations with shell for food helps combat later pests that are made of chitin. Also doubt you're just guaranteed higher brix levels by using shell as an additive, I'm sure there's more to the story where you got that info..

kermit2692 said:

Bugs do not hate chitin they are made of it lmao... The reason it's helpful is there are microbes of some sort that feed on chitin so boosting those populations with shell for food helps combat later pests that are made of chitin. Also doubt you're just guaranteed higher brix levels by using shell as an additive, I'm sure there's more to the story where you got that info..

Click to expand...

I never said guaranteed to get you higher brix readings... I said it might, or it helps to get a sar response from the plants. I couldn't remember which...

Please explain what a sar response is. Never heard that before