Fungus gnats in cannabis cultivation
Fungus gnats appear in marijuana crops when the growing medium remains too wet. Their larvae, which live in the upper layer of the substrate, damage fine roots and especially affect seedlings and cuttings. Yellow sticky traps and the potato test are used to detect them. Control is based on adjusting irrigation, improving drainage, keeping the area clean, and applying biological control such as Steinernema feltiae, Bti, or predatory mites. With good practices, it is possible to keep the pest under control without using chemicals.
