To reduce fungus gnats, correct overly wet potting conditions, let the soil surface dry when appropriate for the plant, and use yellow sticky cards to monitor flying adults. The larvae develop in moist organic material, so traps alone rarely finish the job.
Confirm you have fungus gnats
Look for slender, dark, mosquito-like flies that lift off when a plant is moved or watered. Their presence around potting soil is a stronger clue than tiny flies seen by fruit bowls or trash bins.
Adjust the moisture cycle
Check whether the pot drains freely and whether water is collecting in a saucer. Let the upper soil layer dry between waterings for species that tolerate it; do not apply the same drying advice to moisture-loving plants or delicate seedlings.
- Empty standing water from saucers.
- Avoid constantly damp surface soil.
- Use a potting mix and container that drain appropriately.
Use sticky traps to track adults
Put a yellow sticky card near the potting medium, out of reach of children and pets. The card helps catch adults and shows whether activity is declining. It does not kill larvae that remain inside soil.
When more control is needed
If populations remain high, look for a horticultural product specifically labeled for fungus gnat larvae and follow its directions; some biological controls are available. Avoid indiscriminate household insecticide use and do not soak the pot with unapproved chemicals.
Frequently asked questions
Are fungus gnats the same as fruit flies?
No. They differ in appearance and breeding location, so solving a fruit-fly problem does not necessarily solve a houseplant problem.
Will repotting fix it?
Fresh, appropriately draining potting mix may help when the old mix is saturated, but correcting how you water is important for lasting results.
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