Identify, Treat, Control and Prevent Mealybugs on Houseplants

In the same suborder as scale and aphids, mealybugs have the same sap-sucking mouth parts and honeydew secretions. One big difference between the mealybug and other scale insects is that female adults have legs and can move about the plant. However, the males have wings and are the primary way that the insect spreads from plant to plant. There are 275 known species in the United States alone. Many species of mealybugs have a preference for certain types of plants, especially citrus trees. Ferns, cactuses, orchids, and gardenias are among their favorite plants. Learn how to identify and what to do about mealybugs on houseplants.    

How to Identify Mealybugs on Houseplants

No bigger than 1/4 inch and often as little as 1/16 inch, these bugs can be seen by the naked eye only when they are moving or when their white appearance offers a stark contrast against the green plant material. They look white due to their protective fuzzy-looking covering, but their bodies are actually a pink or yellowish color. They can be quite active shortly after being born while in their crawler phase. As they mature into adults and find a viable feeding spot, they don’t move around as much. When given the chance to breed, these bugs will stunt growth and cause discoloration to houseplants. They also secrete honeydew that can attract other pests or allow mold growth to get a foothold. They are known for being particularly destructive as a houseplant pest.

Mealybug Pest Control and Treatment

There are plenty of insecticidal soaps, oils and sprays for mealybug pest control. Sometimes, isopropyl alcohol may be just as good as killing mealybug on the spot. The problem is mealybugs have a way of finding the folds in leaves and stems that make it hard to hit them directly with these products. Mild infestations can be effectively treated in the short-term, but enough bugs are likely to find hiding places that it’s hard to get rid of them completely, especially in a single treatment. A better plan long-term may be to introduce predator bug, like ladybugs or lacewings. If you know you’re dealing with mealybugs, however, the cryptolaemus bug is sometimes called the “mealybug destroyer.”

How to Prevent Mealybugs on Houseplants

Like all pests, mealybug prevention starts with solid houseplant care. More than just root rot, overly moist soil can attract plant pests including mealybug. Be sure to carefully inspect any new plants before introducing them to the rest of your cherished houseplants. Be wary of putting previously infested plants too close to other favorite houseplants. Many insecticidal products are also great preventative treatments. Reintroducing or maintaining cryptolaemus bugs can also be an effective long-term deterrent.

Cost-Benefit Analysis of Treating Houseplants for Mealybugs

Finding mealybugs on houseplants is one thing. Treatments can be quite effective for mild-to-moderate infestations. It’s another thing if you also see ants. More common with outdoor plants, mealybugs and ants can sometimes attack plants as a co-infestation. Ants protect mealybugs from parasites and natural predators like ladybugs. If you discover ants and mealybugs, it may be time to throw out the plant and take steps to make sure these pests don’t spread to nearby houseplants. Not sure if what you’re seeing is mealybug damage? Check out our complete guide on identifying and controlling houseplant pests.