Problem with fungus gnats

First time grower. Inside plants. Became infested with gnats. Is there a way to save the plants or is it a loss and start over. Any help will be appreciated.

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The best product is BTi. It’s in mosquito bits, but the best place to buy it is ebay. 2 oz is like $16 and more than you need for an infestation or two.

There are many google solutions, but BTi is the only thing that’s worked for me.

Don’t give up, use this, and in a few weeks it’ll be like nothing ever happened.

Stop overwatering also…
That’s why you have them…:wink::+1:


I used neem cake on my house plants when I had this problem over the summer and it doubles as a fertilizer. I would assume although, I don’t like to assume anything, it may work. See what others think.

I used sticky paper and they were gone in 4 days without using any additional products. BUT you have to deal with the source. Find out where those lil fackers are coming from and deal with it.
And yes, it sounds like you are overwatering a bit so go eeeaassyy. Your girls don’t like to sopping wet. :wink:

I had them my first grow so here is what to do.

#1 stop watering and let the soil dry out, your over watering.
#2 you need to buy yellow plant sticky paper and ditmashous eath ASAP.

Place a nice layer on the top of your soil with the DE and put a bunch of those sticks all around the base, tent sides and any problem areas.

Gnats life cycle is larva in the soil, so sometimes you’ll get it in rich soil mixes (you can help solve this by pouring boiling water in your pot the first time you fill it prior to planting your seeds, or some people bake their soil)
Once the larva hatches it goes to the surface and the gnat then finds a mate and pla ts eggs in the soil to rinse and repeat.

Gnats like moist soil so if you don’t have fabric pots and if your watering to often this will be an issue.
The yellow stickys will trick the flying mature gnats that they are flowers and fly onto it thus dieing. The DE spread on the soil surface is microscopicly sharp thus cutting the gnatts and their larva.
So you need both and water very carefully as to keep the layer of DE on the soil top all the time.

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I put a couple of venus flytraps in the tent because I started to have a problem with gnats and I just happened to see them at Walmart on sale. I figured, “Why not”?