University of Illinois Extension

University of Illinois Extension

Hort Answers

Insect Damage


2 (1 = rare 5 = annual)
3 (1 = very little damage 5 = plants killed)
Attacks numerous house plants, some perennials and a few trees and shrubs.

Plants Affected
Mealybugs typically are coated with a white waxy substance that covers the insect. When plants are grown in very loose/porous soils, there are oftenmealybugs feeding on the roots as well as the above ground portions of the plant. Feeding damage can cause distortion of leaves and death of plants especially small herbaceous plants grown outdoors or as house plants. These insects can cause plants to feel sticky due to the honeydew they produce.

Life Cycle
These insects usually feed on the underside of leaves, where leaves attach to stems, or at the base of whorled leaves as well as on plant roots. When the mealybugs congregate in masses, they cause the plant to look "cottony" in spots. In addition some of the "cottony" masses may be egg clusters.


Mealybugs are difficult to control, especially when they are feeding on plant roots. In addition the waxy coating on eggs and the insects help protect them from insecticides. If there are only a few on a houseplant, crush them or carefully wipe them off the plant. If theinfestation is severe, it is much easier to destroy the plant and get a new one. Also most mealy bugs get on house plants because the plants were taken outside for the summer or sometimes just for a day or two. Minimize mealy bugs on houseplants by NEVER taking the plants outside. Use suggested insecticides according to all label directions and precautions.

Outdoors on hawthorn, mealybugs are commonly more noticeable than harmful. Large infestations can cause leaves to turn brown and young stems to die. Usually, treatment is not needed because large infestations are uncommon.

Related Resources
Home, Yard & Garden Pest Guide
Illinois Commercial Landscape and Turfgrass Pest Management Handbook
U of IL - Distance Diagnosis through Digital Imaging
U of IL - Plant Clinic