The mealybug, a common pest on houseplants and fruit trees, looks like a miniature sowbug covered in white powder. The two most common species in North America are the citrus mealybug (Planococcus citri), an import from Europe, and the long-tailed mealybug (Pseudococcus longispinus).
Damage
Like aphids and scale insects (to which they’re related), mealybugs suck out a plant’s juices, causing leaves to yellow and drop.
Control
To control mealybugs, rub or spray them off of the plant, or wash plants with soapy water. Most insecticides are not effective in the egg or adult stages because of the mealybug’s waxy coating.
Know when to fold ’em
If you can’t control an infestation, get rid of the infested plant before the mealybugs spread to other plants.
—photo courtesy of the Kemper Center for Home Gardening at the Missouri Botanical Garden.