Soil flies

The fungus gnat, also known as the sciarid fly (Sciaridae), is a common insect pest in greenhouses and container crops. These flies are usually black or grayish in color, measuring around 2-4mm in length.

The females lay their eggs in the soil or growing medium, where the larvae develop. Fungus gnat larvae are tiny and transparent, measuring about 3mm in length. They feed on decaying organic matter in soil and growing media, but can also damage the roots of potted plants. Fungus gnat larvae can cause significant damage to plants by inhibiting plant growth, causing yellowing or wilting of leaves, or death.

The fungus gnat has a short lifespan, usually about two weeks. Adult flies are attracted to decaying organic matter and can reproduce quickly. Populations can therefore increase rapidly if control measures are not taken.

Fungus gnat control can be difficult, as the larvae are often hidden in the ground and can be difficult to detect. However, signs of an infestation can include adult flies flying around potted plants, as well as larvae crawling on the surface of the soil or growing medium. Biological control methods, such as using predatory nematodes or pathogenic fungi to attack the larvae, can be effective in controlling infestations in a sustainable and environmentally friendly way.

Other control methods include the use of sticky traps to capture adult flies, as well as crop rotation and regular cleaning of pots and growing equipment to eliminate food sources for larvae.