Those Annoying Little Bugs Aren't Fruitflies, They're Fungus Gnats ...

Feb 17, 2014 — by Martha Foley (Retired (2019) News and Public Affairs Director) , in Canton, NYIf you could actually see the little suckers, this is what a fungus gnat would look like. You're welcome. Photo: Peter Ruhr, Creative Commons, some rights reserved Listen

Feb 17, 2014 — The little things flying randomly around your office? They're most likely fungus gnats, an annoying pest that lives in the soil of potted plants. They eat fungus in the soil, and overwatering gives them a lovely habitat to thrive in.

Cooperative Extension horticulturist Amy Ivy says fungus gnats aren't much of the threat to the plant, and there are ways to control them.

Fungus gnats are a symptom that you're not watering your houseplants properly, so the first thing to do to combat the little darlings is take an inventory of your plants' drainage: Do your pots have good drainage? Are you letting the water sit in the saucer? If there's a problem, you need to repot those plants so the little darlings don't have a place to go.

The soil will be full of fungus gnat larvae, so get rid of that and knock as much as possible off the plant. Scrub out the pot and repot using fresh potting mix, which is for the most part sterile.

That and a new watering policy should really make a difference, but if you just repot the plant without changing the watering plant, or if you don't shake off enough soil, the gnats will return.

You can also make a sticky trap to get the adults as they return to the plant to lay the next batch of the eggs. Something yellow smeared with a nice thick layer of petroleum jelly, placed flat on the rim of the pot sticky side up, will do the trick as they'll be attracted to the yellow color. To get the larvae, cut a raw potato into a French fry shape and stick it into the pot. They'll be attracted to that and start eating the potato, and you can just pull them out along with it. It's a great science fair project!

And there's no point in spraying insecticide around the room, because the larvae are in the plants. So you'll only be spraying yourself.

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garden · gardening · outdoor recreation · amy ivy