If you have noticed tiny specks dancing across the soil of your houseplants after watering or repotting, you probably have an infestation of springtails or mites.
Springtails may be white, brown, or gray and are 1/16" to 1/4" long, and jump when disturbed. When watering the plant, they jump 2 or 3 inches into the air, many times jumping out of the pot.
Soil mites may be tiny and whitish, or larger and brownish in color. The size of these mites varies from pinpoint size that can barely be seen to giants almost 1/8" in diameter. If magnified, you can tell that they have eight legs instead of six as in springtails and other insects.
Mites are most common near the surface of the potting soil and will be seen crawling on top of the soil or around the rim of the pot when the plant in watered.
Both springtails and soil mites feed on the peat moss, leaf mold and other decaying plant material in the soil mix. Some of the mites will be predators, feeding on the springtails and other mites that are present. Since these creatures do not feed on the plant, they are only nuisances and will not affect the health of the plant.
Fungus gnats appear as white larvae about 1/8" long in the soil mix. They emerge from the pot as small, black flies about 1/8" long that fly around the home.
Fungus gnats larvae feed on decaying plant material in the soil mix as do springtails and soil mites. They will also feed on the roots of the plant and may kill seedlings or other young plants. Established plants are usually not harmed.
Springtails, soil mites, and fungus gnats can be controlled by allowing the soil to dry out between waterings, not keeping the soil moist.
Repotting the plants using a sterile soil mix and a clean pot will also eliminate these creatures. Soak the roots of the plant for a short time in water to remove as much of the old soil as possible. Repot quickly so that the roots do not dry out. This procedure can be quite drastic and result in death if the plant is not handled carefully.
Insecticides can also be used to control these creatures. Contact your local U of I Extension office for the current recommendations. Always follow label directions.
Author: David Robson, U of I Extension Educator, Horticulture, Springfield Center, (217)782-6515
