Preventing fungus gnats in Click and Grow

About three weeks ago, I transplanted 4 of the extra seedlings from my yellow mini tomato pods into separate pots with brand new potting soil. Over the past few days, I’ve noticed small black flies flying out of the soil of the new pots when I water. From a quick Google search, it sounds like my transplanted yellow tomatoes have fungus gnats. I’m planning on starting with sticky traps for the adults, purchasing a soil moisture meter to prevent overwatering, and putting a layer of gravel on top of the soil. Then I’m going to try insecticides if the infestation continues.

However, I’m wondering if anyone has suggestions on preventing the fungus gnats from moving from my pots into my Click and Grow pods. What would be the best way to prevent this? Can insecticides be used with the Click and Grow garden as well?


Hi @Catherine,

I also have struggled with fungus gnats in regular pots. And it helped if I let it dry out without killing the plant and cleaned up stagnant water under the pots. If the environment changes to unfavorable it clears out.
I would not use insecticides on the plants which bear fruits that I intend to eat later. In my experience fungus gnats don’t harm the plant in a severe way to affect plant health.

Though, it seems you are already doing everything to get rid of gnats.

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Cheap, easy and effective method of getting rid of fungus gnats: ZERO ANT POWDER - S$5.35 for 150g from Hua Hng World Farm - extremely cheap solution because you need only a tiny bit to solve the problem. It contains a synthetic pyrethroid that is harmless to humans and animals (except fish). Simply dust a little of this powder anywhere you find fungus gnats, flies, ants, roaches etc… and you won’t find them around after that. Dust a little over the soil surface of the soil and bottom water after that. There are currently 2 batches of them in the market - one has a carrier powder that disperses in water and the other doesn’t. If you get the one that is dispersible in water, you can even mix some of it in a glass of water and pour it into your soil and it kills the eggs, larvae, pupa and adults upon contact.

Pyrethroids are commercial household insecticides, I would not claim it is harmless to use in indoors systems, especially on or near edible plants.

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