Pest
Fungus gnats
Fungus gnats are small dark flies that breed in consistently moist potting soil. The adults are mostly a nuisance, but their larvae can damage fine roots on young or weak plants.
How to confirm it
- Check whether the flies show up mainly when the soil surface is disturbed or watered.
- Confirm the top of the soil has stayed damp for several days in a row.
- Look for small worm-like larvae in the top inch of soil if you dig gently.
Next Steps
Fixes connected to this cause
Control fungus gnats
Fungus gnats breed in wet soil, so drying out the top layer between waterings matters more than any trap.