October 24, 2024 – Mealybugs (there are 4 varieties) are tiny scale insects resembling tiny puffs of cotton that suck sap from the flower and vegetable plant leaves and stems. In small invasions, they are hardly visible, cause no noticeable damage and can be removed by a strong stream of water, something not possible in larger infestations. As they multiply, however, the “cotton” appears to grow, with enlargement visible on a daily basis. They cannot fly, but plant crowding makes it easier for them to spread to other plants.
In larger numbers, they can overwhelm leaves causing them to die and drop, eventually killing the plant. They can occur anywhere on the plant, but are usually more noticeable on leaves. They can be particularly dangerous as you decide to move plants inside for the coming winter, an ideal environment for multiplying and destroying.
Mealybug prevention is best and can be achieved by having strong, healthy, resilient plants. Mealybugs like plants with a high nitrogen content and lots of new growth. Too much water and too much fertilizer make infestations worse. If you notice any white spots on plant stems or leaves, pick them off and squish them, or if indoors, drop in a waste basket.
The simplest way to kill mealybugs in your home is spraying the plants with a 50-50 mixture of water and alcohol in a spray bottle. Dusting infected plant with diatomaceous earth works very well, but you might want to take the plant outside first!
Horticultural oil sprays, insecticidal soap sprays, and homemade sprays will all kill mealybugs, but check with your county extension agent for mixture ratios. You can purchase ladybug beetles to feast on the mealybugs. Each beetle can consume up to 250 mealybugs during its lifetime. A Neem oil spray will repel but not kill them.
