African Violets and Insects

African violets are a good choice for homeowners who wish to grow plants indoors, because these plants thrive under indoor lighting conditions. While African violets are generally healthy, they are susceptible to insect infestations affecting their beauty. Spider mites and mealybugs are the two primary pests of African violets. Chemical control methods may be necessary if your plant is heavily infested with insects.

Spider Mites

• Spider mites are members of the Tetranychidae family that have eight legs, an oval body and no antennae. Spider mites are very tiny and difficult to see on houseplants without a magnifying glass. African violets are favored hosts of spider mites, and infested plants suffer from the effects of spider mite feeding. Spider mites can cause leaf stippling, yellowing or bronzing and heavy populations can cause the host plant to become stunted. Spider mites multiply at a rapid rate, often completing the development from egg to adulthood in less than seven days. The presence of silky webbing on African violet leaves and flowers is a symptom of heavy infestation.

Spider Mite Control

• Examine your African violet for spider mite infestations by looking at the undersides of leaves with a magnifying glass. Mites tend to congregate and feed in these areas. If a few mites are found, you may be able to control them by spraying your African violet down with a hard stream of water, causing the mites to fall from the plant. Your houseplant should be sprayed twice each week for optimal control. Heavy spider mite infestations are more difficult to control. Horticultural oils are available at your local garden center and are often an effective means of mite control. These products work by covering the air holes of the mite, causing them to smother. Miticides are another chemical control method recommended for spider mites. When using either types of chemical control methods, it is important to cover the entire plant thoroughly for best results. Treat all houseplants at the same time to prevent infestation of other indoor plants.

Mealybugs

• Mealybugs are another common African violet pest. This pest closely resembles sowbugs and is very small, measuring no larger than 1/15th of an inch in length at maturity. Mealybugs received their name for the waxy coating covering their backs, which resembles ground meal. Mealybugs is related to aphids, whiteflies and scales which are common pests of many indoor plants. African violets infested with mealybugs often suffer feeding injuries, such as yellowing of leaves and leaf drop. Severe infestations may cause the houseplant to die. Mealybugs produce a substance that causes sooty mold to develop. African violets with sooty mold develop a coating of black fungus on leaves and flowers. Although sooty mold is usually not harmful to plants, many homeowners consider it unsightly on their indoor plants.

Mealybug Control

• If only a few mealybugs are present on your African violet, you can remove them by hand by placing a cotton ball in alcohol and dabbing it on the bug. Washing your indoor plant with soapy water can also control light to moderate mealybug infestations. Large numbers usually require insecticidal sprays to control infestations. Reapply insecticides for optimal control. If mealybugs cannot be controlled, it may be best to discard your plant to prevent infestation of other plants in the home.