UC Master Gardeners, Santa Clara County, CA
University of California
UC Master Gardeners, Santa Clara County, CA

Monthly Tip

Fungus Gnats

Tip description

Fungus gnat, C. D. Armstrong, University of Maine
Have you ever found yourself waving away a poorly-flying, small insect near seedlings or houseplants? Or noticed a swarm of tiny flies around a composting bin? Adult fungus gnats are nuisance pests, but in high numbers, the larvae can damage roots and stunt plant growth. They thrive in moist, organically-rich potting soil and can be found indoors at any time of year. The most effective control targets the larvae by eliminating excess moisture, especially by letting the surface of container soil dry between watering. Other control methods are discussed in the linked UC Pest Note.

For more information: Fungus gnats Management Guide

Months applicable
  • May
  • June
  • July
  • Any month
  • 3. Pests and Diseases

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