Fungus gnats don’t start as a “flying bug” problem. They start in the soil.
- Adults — Tiny black flies hover around plants and lay eggs in moist potting mix.
- Eggs — Eggs hatch fast when soil stays damp.
- Larvae (the real issue) — Larvae live in the top layer of soil and feed on fungus and tender roots. This is where plant stress can begin.
- Pupae — Larvae turn into pupae in the soil.
- New adults — New adults emerge and the cycle repeats—quickly.
How to break the cycle (larval control):
- ✅ Let the top 1–2 inches of soil dry between waterings
- ✅ Remove decaying leaves + organic debris on the soil surface
- ✅ Use yellow sticky traps to catch adults and monitor activity
- ✅ Target larvae in the soil with a larvicide labeled for fungus gnat larvae like Mosquito Bits® with Bti. (follow label directions)
Key takeaway:
- Sticky traps reduce adults, but larval control is what stops the next wave.
- https://summitchemical.com/fungus-gnats/
Fungus gnats don’t start as a “flying bug” problem. They start in the soil.
