Whiteflies: Pests Closely Related to Aphids, Scales, and Mealybugs

Whiteflies are tiny winged insects 1/16 inch (2mm) long or smaller with a powdery white appearance. They belong to the same group of insects as aphids and scales and reproduce rapidly during the summer. 

They gather on the undersides of leaves and flutter off in a cloud when disturbed.

Females lay their eggs underneath leaves and produce nymphs in about 12 days. These nymphs are pale, flat, scale-like insects that do not move. They also feed by sucking plant sap.

They have sharp mouthparts that pierce plant tissue and suck juices from plants, leading to wilting and stunted growth.  These insects excrete a sticky gel called honeydew which encourages the growth of a black fungus called "sooty mold".  

This black coating blocks the leaf pores and prevents photosynthesis. Plant damage results in yellowing, deformed leaves, and plant death.
After destroying  the insects, wash leaves to remove the unsightly mold with a solution of dishwashing detergent and water.  Insecticidal soap will clean the leaves as well as the pests.

How to Get Rid of Whiteflies:

1. Use yellow sticky tape to trap them.

2. Vacuum flying adults from the air and make sure none of them escape from the vacuum bag. You can cover the vacuum cleaner's hose attachment with netting to prevent damage if you get close to your plants.

3. Wipe off nymphs with a damp cloth or use cotton swabs dipped in rubbing alcohol to remove them. They are pale, flat and difficult to see without magnification.

4. Thoroughly spray both sides of leaves, stems, and soil with insecticidal soap for serious infestations. Insecticidal soaps are
available on the market (such as Safer's Insecticidal Soap).

5. Spray plant with a solution of neem oil. The oil has systemic benefits and doesn't need direct contact with the bugs. It works as a pest repellent and a fungicide to control powdery mildew. It also affects their life cycle by stopping reproduction of the flies.  It is non toxic and can be used on vegetables as well as ornamentals.

6. Keep plants healthy and stress-free to fight off these destructive pests. You should always act immediately to  control pests.

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