Aphids: Houseplant Pests Commonly Known as Plant Lice

Aphids are 1 /8 inch (3mm) long sucking insects that may be green, gray, brown, or black. They are soft, round-bodied with a long beak coming from between the forelegs, from under the head, which is used to suck the sap of plants.

These insects reproduce very quickly and form in large clusters. This causes the plants to become infested quite rapidly, killing the new growth.

They suck the sap from the plant's leaves and stems and secret the excess sugar called honeydew.

Plant becomes weak with pale deformed leaves and blooms.  New growth is stunted or deformed. Plus, they attract ants and spread plant viruses.

aphids on a leaf

The most important step in control of these pests is early detection. Inspect plants often and treat as soon as pests are found.

Look for them along stems, especially at the tips, flower buds, and leaves. Honeydew is an early indicator of infestation. If you sees any of these signs on your houseplants, take action to deal with them immediately.

Always isolate newly purchased plants from your other plants for two weeks or more to determine that they’re pest-free before you bring them home.

Treatment for Lice on Houseplants

1. You can use a cotton swab dipped in isopropyl alcohol to remove the insects. This application must be repeated every two to three days to be effective and do not cover the whole leaf with alcohol. It could damage plant tissues. Use this treatment on African violets.

2. Wash plant with warm soapy water and rinse. Do not use this treatment on African violets--they tolerate no moisture on their leaves. Use two teaspoonfuls of mild dishwashing liquid without any additives in a gallon of water to make a plant wash.

3. Add systemic granules to the soil to control these pests
of African violets and other plants that don't like water on their leaves. The insecticide is absorbed through the roots throughout the plant. This even protect the new growth.

4. Spray with a strong stream of water to remove the tiny white bugs on plants.

5. Spray with insecticidal soap if there are large number of insects on the plant. Let soap remain on plants for 30 minutes and rinse to remove the residue.

Caution: When treating any houseplant for pests with insecticides, read the label carefully and use outdoors when possible. Keep all pesticides out of reach of small children and pets.