Fungus gnats are common indoor pests. Adult gnats are about ⅛" long, grayish to black in color, with long legs, antennae and one pair of wings. The adults do little plant damage, but can be unpleasant if they are present indoors in large numbers. The larvae live in the soil and chew on plant roots.
Control Fungus Gnats
Fungus gnats look like little mosquitoes, only they don't bite. In fact, they're so small, you may not even notice you have any unless they swarm. Fungus gnats hang out in damp soil and live off decaying organic matter. That's why they love greenhouses and houseplants. If you see them flying around your African Violets, clearing debris from near your plant helps to control them.
Watch Your Watering
Fungus gnats like moist areas. Make sure your containers have good drainage, and avoid keeping your plants too wet. Let the top 1-3 inches of soil dry before adding more water. Keeping the top of the soil dry will help stop fungus gnats from laying their eggs in the soil. Also, be sure to empty excess water out of the saucers under your container plants.
Potential Home Remedies
Try adding a ¼ inch of horticultural sand (do not use play sand) to the top of your containers to help prevent fungus gnats from laying eggs in your containers. You can also place the cut side of a potato on the soil surface to draw some of the larvae out of the soil.
Use a Control
To kill the pesky gnats flying around your house, use Ortho® Home Defense® Fly Bait Decal for Windows. You can control fungus gnats in your container plants with Ortho® Rose & Flower Insect Control Plus Miracle-Gro® Plant Food Granules. It feeds and protects for up to 8 weeks. For best results, always follow the instructions on the label.