Help! My houseplant has mealybugs! What should I do!?
Mealybugs are a common problem for houseplants. There are many ways to get rid of mealybugs on plants, but the most effective is to use an insecticidal soap spray. This will kill all stages of the mealybug and prevent them from coming back. Keep reading for more information about how to identify, get rid of, and prevent mealybugs on your houseplants!
What are Mealybugs?
Planococcus citri, commonly known as the citrus mealybug, are a houseplant parent’s nightmare. Mealybugs are white, small, soft-bodied insects and common household plant pests that feed on plant juices. It’s easy to mistake mealybugs for fungus and mildew due to their fuzzy white appearance. However, mealybugs are related to scale insects, which are brown. There are over 300 species of mealybugs in the United States.
Adult mealybugs are 1/10 to ¼ inches long, have a distinct oval-shaped body, and are covered in white mealy wax. They secrete the white powdery waxy that gives them the characteristic white cottony appearance. The white layer protects these houseplant pests from heat, moisture loss, and water-based insecticides.
Like most insects, mealybugs have short production cycles, about 7 to 10 weeks. Adult females can lay hundreds of eggs without mating, and they die soon after. The eggs resemble white fuzzy masses and hatch within ten days into small yellow nymphs.
The nymphs crawl all over the plant, searching for feeding sites. They secrete honeydew, a sticky substance, as they feed, and a waxy coating forms over their bodies. Nymphs morph into adults in 6 to 9 weeks, depending on the temperature.
The short life cycles mean the mealybug population can burgeon quickly if left unchecked. However, due to the small sizes of the eggs and nymphs, light infestations aren’t usually noticeable until the population explodes.
Mealybug species are common in the warm weather of the northern regions, where they pose a significant threat to houseplants and greenhouses but hardly affect outdoor plants. However, these tiny white bugs pose a severe threat to crops growing in warmer climates.
Mealybugs damage plants by sucking the plant sap from stems and leaves, but they often favor the softer new growth. Significant damage results in leaf yellowing, stunted plant growth, and eventual dieback.
As mealybugs feed, they produce honeydew which attracts ants and encourages the formation of sooty mold. Left untreated for a long time, a mealybug infestation will eventually kill the host plant.
How to Get Rid of Mealybugs on Houseplants
Exterminating female mealybugs is a tricky and tedious process, especially when dealing with a large pest infestation. It’s a good idea to move fast after noticing the presence of mealybugs on your indoor plants. Heavy infestations of mealybugs on houseplants are notoriously difficult to treat.
Mealybugs are just one reason when you bring any new plant into your home that you carefully inspect it for pests and keep it away from your other plant babies for 2 weeks. I always spray mine down with insecticidal soap or neem oil regardless if I see any pests just in case.
Why do plants attract mealybugs?
Plants attract mealybugs because they provide food, shelters, and breeding grounds. Mealybugs love moisture and readily invade overwatered and overfertilized plants. These bugs are attracted to plants with soft tissues, high nitrogen levels, and plant juices. African violets, orchids, coleus, begonia, and amaryllis are among the most susceptible houseplants.
|Pictured below is a plant at an outdoor patio near our house. I immediately noticed it when Caleb and I were enjoying our brunch. Poor plant! I wanted to take a photo so you could see that mealybugs can be a problem on your outside plants, too!|
If you notice white fuzzy splotches on your houseplant, you have mealybugs. White cottony masses on indoor plants are the first sign of a mealybug problem. Mealybugs hide in new leaf folds, on the underside of leaves, and around the plant’s growing tips. Sometimes they hide in leaf whorls, stem crevices, and other hard-to-reach places.
Mealybug Control and Removal Techniques
There are many control techniques to help you get rid of mealybugs on houseplants, including:
- Pruning: You can prune the affected plant parts and dispose of them if you’re dealing with a mild mealybug problem. But you should treat the rest of the plant to keep the pest from spreading to new plants. It’s ideal when dealing with low pest levels.
- Wash the plant: A forceful spray of lukewarm water on infected plants can dislodge the individual mealybugs, egg sacs, and cottony masses. However, periodic washing is necessary since this method isn’t 100% effective.
- Isopropyl alcohol: Soak a cotton swab rubbing alcohol and rub it against the affected plant’s stems and leaves. Rubbing alcohol kills mealybugs on contact, so you must touch them directly. Q-tips are ideal because they let you reach into the leaf joints and folds. Unfortunately, it may take several repeat applications to eradicate the houseplant pests.
- Insecticidal soap: The best way to deal with a mealybug attack is to spray an infected plant with insecticidal soap. Insecticidal soap is a short-lived natural pesticide with no residual effect that kills mealybugs in hours. However, the solution damages the protective layer on their soft bodies, leading to dehydration and quick death. Mix the soap with water in a spray bottle following label directions and apply it to the houseplant.
- Neem oil: Since it’s a natural insecticide and fungicide, neem oil is an excellent mealybug destroyer. It’s non-toxic and has antifeedant and repellent properties. It disrupts mealybug growth and development without harming beneficial insects. You can apply the oil on the using small pieces of cotton.
- Soap spray: Dish soap is a contact insecticide that breaks down the protective white coating on mealybugs and their egg clusters. You must coat the bugs and the eggs with soap spray to kill them. Be sure to use a dilute soap solution to avoid harming the plant.
Mealybug Prevention Tips
Keeping your plants healthy makes them less susceptible to a mealybug attack as they’re less likely to attract pests. However, stressed and underpotted plants are too weak to withstand an attack and often experience significant dieback.
Here are proven ways to prevent a mealybug infestation:
- First, cut back the watering and fertilizing schedule to reduce the nitrogen levels and allow the growing parts to harden.
- Spray or wipe down the foliage of susceptible plant species with a neem oil solution
- Blast the hardy plants with a hand-held sprayer to dislodge the pest and its eggs.
- If your plants can handle the temperature variation, drop the temperature to 60°F to make the room unconducive to mealybugs, which thrive in tropical temperatures.