Fungus Gnat Control – Fungus Gnats In Houseplant Soil

Image by JR Guillaumin

By Heather Rhoades

Fungus gnats are not a common houseplant pest, but when these little fly like creatures invade your houseplant’s soil, they can become a serious nuisance. These soil gnats thrive in damp, dark places that are full of organic materials; this makes potting soil a perfect location for them to multiply. Keep reading to learn more about how to get rid of fungus gnats.

Identifying Fungus Gnats

Fungus gnats are very small fly like insects. While many people may mistake them for flies, their body shape has more in common with mosquitoes. These soil gnats bodies are long and thin and their legs are long.

Their maggots look simply like long white or transparent threads in the soil, no longer than ¼ inch.

Fungus Gnat Damage

The biggest threat from fungus gnats is the fact that they live in the soil and will feed on the roots of the houseplants whose containers they have invaded. This fungus gnat damage to the roots will cause a plant to wilt or become stunted. In a plant that is heavily infested with fungus gnats, you may see the plant start to yellow or even die.

Fungus Gnat Control

The most common form of fungus gnat control is to apply a pesticide to the soil of the infected plant. Any pesticide listed as being effective on gnats will work. Often these gnaticides will contain pyrethrins, but there are several insecticides that will also work.

If you are looking for an organic fungus gnat control, the best option is to repot the plant in gnat free soil. Remove the plant from the infected soil and wash all of the soil off the roots of the plant. Wash the container that held the infected plant in a weak solution of bleach water. This will kill any eggs or larva still in the pot. Repot the plant in fresh soil and allow the soil to dry out in-between watering to prevent reinfestation of the soil gnats.

Fungus gnats are annoying, but once you know how to get rid of fungus gnats, you can keep this pest from bothering your lovely plants.

This article was last updated on

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