White flies also are small and white, but unlike mealybugs, will take flight if you shake the plant. They come in quantities and can spread to all the plants in your house. Spider mites are miniscule but very destructive. An infested plant will have yellow-speckled leaves and may be covered with tentlike webs. They're easy to spot if you hold a piece of white paper under the plant and shake the leaves so the mites drop onto the paper.
Scale appears as blister-like areas on stems and the undersides of leaves.
Scale also produces honeydew, which may drip from the leaves. Rinsing the plant under a gentle stream of water for a few minutes can wash away insects and eggs. Keep checking the plant for a recurring infestation during the next couple of weeks. It's also important to gently dig around the roots and look for pests in the soil, such as sow bugs, millipedes and slugs. You can remove most of these by hand, or you may want to rinse the soil off with a garden hose and repot the plant in new soil.