I've been dealing with a major fungus gnat infestation ever since I repotted several plants about a month ago using some inexpensive potting soil that turned out to be infested. I've tried numerous methods to control them, including sticky traps, mosquito bits in my watering, letting the soil dry out, insecticidal soap, neem oil, and even systemic granules. Just this weekend, I repotted with fresh, safer soil and thoroughly cleaned the pots and roots.
Although I've seen some improvement, I'm still noticing these little pests everywhere! The sticky traps I initially set up caught hundreds during the worst of it, but even with the new traps, I can still see them. I'm at my wit's end and could really use some more advice on effective ways to finally eliminate these gnats!
2 Answers
Try making a gnat tea with your mosquito dunks or bits. Just soak them in water and use that to water your plants weekly. It actually works wonders for controlling the population!
You’re not alone! Cheap soil is often the culprit, but gnats can hitch a ride on any bag. Next time, let the soil sit outside for a few days to air out before using it; that can help reduce the chances of gnats sneaking in again!