Fungus gnats are small and relatively harmless flies. The presence of fungus gnats may indicate overwatering as the flies are attracted to the moist soil to lay eggs. Larvae feed on fungi in the soil and can cause damage to plant roots if the population is high and the roots are in wet soil. Damaged roots may lead to wilting, loss of vigor, poor growth, and yellowing.
Avoid overwatering. Wet soil promotes fungal growth, which serve as food for fungus gnats.
Cover exposed soil with sand to prevent adult gnats from laying the eggs.
Use sticky or pheromone traps.
Inspect new plants for signs of an infestation.
Let the soil dry out.
Apply ecological products for plant protection (e.g. neem oil, horticultural soap, cinnamon).
