Bugs Are Eating My House Plant Leaves

Insect Removal

• Large insects picked up outdoors are easy to remove by hand and usually few in number. Tiny insects that come from commercial greenhouses are often difficult to see and you may notice the damage before you see the bug. You can dislodge many small insects with a strong spray of water from a syringe or by washing the plant with a soft, moist cloth. Mealybugs, which may appear to be a cottony growth on the plant, and scale insects, which look like small tan or brown lumps on the foliage, are difficult to remove from the leaves. You may need to kill them first with a cotton swab saturated with alcohol.

Watering

• Changing your watering routine can eradicate two of the most common houseplant insects: whiteflies and spider mites. Whiteflies are tiny flying insects that rise above the foliage when the plant is disturbed or shaken. They breed in moist potting soil and the larvae feed on roots, causing a general decline of the above-ground parts of the plant. The single best method of controlling whiteflies is to water only when the soil is dry. Allow the potting soil to dry out as much as possible without letting the foliage wilt. Spider mites prefer the opposite environment. They like dry, dusty plants and dry soil. Watch for the webs they build on the undersides of the foliage. Combat spider mites by keeping the soil moist and misting often. It the plant has smooth, glossy leaves, wash them with a soft cloth moistened with a 10 percent solution of mild soap such as dish detergent or baby shampoo. Fuzzy-leaved plants don’t like to get wet, and you may need to use an insecticide labeled for use against spider mites on house plant.

Insecticides

• When natural methods of removing insects from your house plants are ineffective, the use of insecticides is the next step. Make sure the insecticide you choose is labeled for use on houseplants and carefully follow the instructions. Look for sprays that contain less toxic ingredients such as insecticidal soaps, neem oil, horticultural oils, Pyrethrins and pyrethroids.

Inspection and Isolation

• Carefully inspect plants before you buy them. Look for clean, healthy plants without spots, yellowing, or other evidence of insect feeding. Pay particular attention to the undersides of leaves where insects like to hide and the point where the leaves join the stem. Isolate new houseplants for a period of about a month before placing them with other plants. A distance of about three feet is sufficient to prevent the spread of the type insects that breed in commercial greenhouses.