Fungus Gnats
NuisanceWhat it is
Small dark gnats whose larvae develop in moist soil, potting media, and decaying plant material where fungi are present. Indoor activity is often associated with overwatered houseplants.
How to recognize it
Tiny dark gnats flying around houseplants and windows or walking on the soil surface.
Where you will find it
Overwatered houseplants, damp potting soil, and moist organic matter.
Why it matters
Indoor activity usually means overly wet soil. Larvae feed on fungi and sometimes roots.
What to do
- Remove food waste, rinse bins and recycling, and keep trash covered.
- Clean up spills and organic buildup around drains, sinks, and floor areas.
- Note where the flies gather. The location helps a technician find the breeding source.
- Contact a licensed pest professional to find and address the source, since killing adults does not stop the cycle.
When to call a professional
- Flies keep returning after you clean.
- You suspect a drain, sewage, or hidden food source.
- You run a restaurant or food facility.
Related pests
Black Flies
Small, dark, hump-backed flies whose females may take blood meals from people and animals. They usually breed in clean, flowing water and are most troublesome outdoors near streams and rivers.
Read more →Blow Flies
Metallic or dull-colored flies that commonly breed in carrion, animal waste, garbage, or other decomposing organic matter. Indoor activity can indicate a sanitation problem or a dead animal nearby.
Read more →Crane Flies
Long-legged flies that resemble oversized mosquitoes but generally do not bite. Adults are often attracted to lights, while larvae usually live in moist soil, turf, or decaying organic matter.
Read more →Drain Flies
Tiny fuzzy, moth-like flies that breed in the organic film inside drains, floor drains, sewage areas, and other wet sites. Persistent adults usually indicate a nearby moist breeding source.
Read more →This page is general information, not a diagnosis. Pests vary by region and situation, and an on-site inspection is the reliable way to know what you have.