white mealybugs on plant

Mealybug
Whitney Cranshaw, Colorado State University, Bugwood.org

Updated: March 26, 2021

Signs and symptoms of mealybugs on indoor plants

  • Mealybugs are covered with a powdery wax and the body tapers towards the tail.

  • They may have waxy tufts around the body margin and several tails at the rear end.

  • Mealybugs may be found at rest or slowly crawling on the undersides of leaves, on stems in flowers or even on the outside of the pot.

  • Cottony white wax is usually the first sign of their presence.

  • Mealybugs damage plants by sucking sap and their feeding can result in yellowing leaves, stunting, dieback or death of the plants.

  • They secrete honeydew that supports the growth of black sooty mold on plant parts.

mealybug on coleus stem
Mealybugs on coleus

Management strategies

  • Check plants on a regular basis for the presence of mealybugs. Mealybugs that have been parasitized will be darker in color and exit holes may be visible where the parasite emerged.

  • Mealybugs are very difficult to control. Heavily infested plants should be discarded. 

  • Isolate infested plants so the infestation does not spread. 

  • Dipping a cotton swab in household alcohol and dabbing it on the individual mealybugs can control light infestations. Mealybugs treated with alcohol will turn light brown in color. Be careful not to get the alcohol on the leaves of the plants as they may be damaged.

  • For heavy infestations, spray the plants thoroughly with insecticidal soap for indoor plants or a registered houseplant spray. Be sure to follow all directions carefully and make sure that the plant or pest is on the label. Multiple applications will most likely be necessary.

  • The other option is using a systemic indoor plant insecticide that is watered in around the roots.  

  • After treating monitor the plant for mealybugs each time you water. Retreatment may be necessary. 

  • Close-up of a mealybug under a waxy coating

    closeup of a white mealybug
  • Mealybug on a cactus
    Photo: MDA

    mealybug on a cactus