Fungus gnats are small flying insects whose larvae feed on organic matter and plant roots in moist growing media.
WHAT ARE FUNGAL GNATS?
Fungus gnats are attracted to damp soil and decaying organic material. While adult gnats are mostly a nuisance, their larvae live in the root zone and can damage young plants by feeding on fine roots.
They are especially common in organic soils and overwatered containers.
HOW WE GET FUNGUS GNATS
Growers encounter fungus gnats when:
– Soil stays wet for long periods
– Organic matter is abundant
– Drainage or airflow is poor
– Seedlings are overwatered
They are often noticed as small black flies hovering near the soil surface.
WHY IT MATTERS
Fungus gnats matter because:
– Larvae can damage roots
– Seedlings are especially vulnerable
– Root damage slows growth
– Heavy infestations can stress plants
They are usually a sign of environmental imbalance.
LIMITATIONS & NOTES
Fungus gnats are rarely fatal to mature plants but can be persistent. Addressing moisture levels and using integrated pest management is more effective than treating adults alone.