Identify the type of gnat (drain/houseplant fruit fungus vs. sewer/midge) by where they’re most common: sinks/showers, trash, houseplants, or near doors/windows
Stop breeding sources immediately
Remove standing water and wet organic matter
Empty and clean trash cans regularly; rinse thoroughly
Take out garbage and recycling more frequently if gnats are near food waste
Clean kitchen sink drains, garbage disposal, and surrounding areas
Scrub sink areas with hot soapy water and a drain brush
Flush drains with boiling water (safe for your plumbing) and repeat daily for a few days
Use a drain cleaner safe for your plumbing as directed
For persistent drain gnats, apply a biological drain treatment (bacteria/enzymes) to the drain lines as directed
Fix leaks under sinks, around faucets, and near appliances
Dry wet mops, sponges, and dish rags; store them dry
Cover exposed food and keep counters clean
For houseplant gnats: let the top 1–2 inches of soil dry out between waterings
Water from the bottom (so the surface stays drier) when possible
Remove and discard heavily infested soil or top-dress with fresh sterile medium
Remove dead leaves and decaying plant material from pots
Use yellow sticky traps near plants to reduce adult gnats
Apply a soil drench with Bacillus thuringiensis israelensis (Bti) to kill larvae in soil as directed
Use beneficial nematodes in soil as directed for larvae control
Consider a top layer of coarse sand or horticultural grit to deter egg-laying (keep soil surface dry)
Repot plants with fresh potting mix if infestation is heavy
For indoor humidity issues: run dehumidifiers and improve ventilation
Seal entry points around doors/windows; use screens
Vacuum adults daily and dispose of the vacuum bag/contents immediately
Clean areas around pet bowls, wet bedding, and compost bins
If gnats persist after cleanup and treatments, contact a licensed pest control professional