Fungus Gnats (adults and larvae)

Adults are typically found flying around houseplants, greenhouses, and other moist environments with decaying organic matter. Larvae live in the top layers of soil, especially in damp conditions and where fungi or decaying plant material is present.

Adult fungus gnats do not feed significantly and are mainly concerned with reproduction. Larvae primarily feed on fungi, decaying organic matter, and plant roots, especially fine root hairs.

Adults are weak fliers and are often seen near the soil surface of potted plants or attracted to lights. They have a short lifespan of about 7-10 days. Females lay eggs in moist soil. The larvae emerge and feed on organic matter and roots for about 2-3 weeks before pupating in the soil. The entire life cycle can take 3-4 weeks depending on temperature and conditions.

Potential risks include being a nuisance by flying around indoors. Larvae can cause damage to plant roots, especially seedlings, cuttings, and plants that are overwatered, leading to wilting, stunted growth, and even plant death in severe infestations. They do not pose a direct health risk to humans. Benefits are limited, though they can be minor decomposers in their natural outdoor habitats.