Most people that practice indoor gardening, even those that have just a few potted plants they keep inside their home, have come across fungus gnats, common indoor pests of houseplants. These harmless insect pests pose more of a nuisance than anything else, but they can become quite annoying this time of year around late spring when their numbers increase. This is when complaints from homeowners about the tiny, dark-winged fungus gnats hovering around their houseplants streaming in to pest control professionals.

Fungus gnats are 1/16 to ⅛ inch long and frequently misidentified as fruit flies. However, knowing the difference is crucial to knowing why they are hanging around and how to get rid of them. Fungus gnats have skinnier, more delicate-looking bodies and legs in contrast to fruit flies, which look like smaller versions of house flies with their rounder body. They also tend to stick close to houseplants and are unable to fly great distances, so will usually travel no farther from their home plant than the nearest window sill.

Fungus gnats lay their eggs in soil, often that of potted plants. They thrive in moist conditions, such as those found in soil, and feed on fungi, algae, and decaying plant matter, as well as some roots and leaves found resting on the surface of the soil in which they lay their eggs. This means that the more moisture soil has, the more attractive it is to fungus gnats. The main reason fungus gnats are common in homes is because of the moisture levels of indoor houseplants. Believe it or not, overwatering your houseplants is likely the main culprit behind the presence of fungus gnats. They thrive in moisture, and the more houseplants you own, the more likely you are to have problems with fungus gnats.

With the current pandemic forcing many people to work from home, more people are overwatering their plants, which has brought these pests out in full force. The best thing to do is not overwater your houseplants and let the soil dry out between waterings. Houseplants that are brought indoors are also often a source of fungus gnat problems, as they have already been colonized by the pests outdoors. When these plants are brought inside to a warmer environment and exposed to increased moisture, they begin to proliferate and become a problem. The best way to avoid problems with fungus gnats is simply to be more mindful of your watering practices.

Are you seeing more fungus gnats inside your home than usual?