Clusters of mealybugs may look like fur or lint that’s lodged in the forks of twigs and branches, on leaf undersides, and on fruits. That’s because the oval bugs are covered with a protective waxy coating that has a grainy, dusty texture.
Mealybugs suck plant juices from fruit crops, potatoes, and many kinds of ornamentals. Feeding results in yellowing leaves and dark, dirty patches that are actually sooty mold (a fungus) growing on the mealybugs’ sweet excretions, or honeydew. As they feed, some species inject toxins that damage plant tissues.
Mealybugs overwinter in their nymph stage or as eggs that are protected inside cottony egg sacs. In warm regions and greenhouses, mealybugs can be a year-round pest. They are found throughout North America in gardens.Prevention and Control
- Use a strong spray of water from your hose to dislodge mealybugs from plants. Recheck the plants a few days later and repeat the treatment as needed. (Keep in mind that water sprays will also kill beneficial insects.)
- For greenhouse plants or container plants, remove mealybugs by dabbing them with a cotton swab soaked in rubbing alcohol.
- Encourage parasitic wasps that prey on mealybugs.