How to Prevent & Treat a Whitefly Infestation

by Joan Whitman 02/05/2023

Keeping plants at home means contending with the occasional pest. While some garden pests are just an annoyance, others can cause damage and even threaten the life of your plants. One common pest is the whitefly, which can infest both your outdoor garden and indoor houseplants. Here is a guide to everything you need to know about whiteflies:

What Are Whiteflies?

As their name suggests, whiteflies are white-colored insects resembling flies. They're slightly triangular in shape and can be smaller than a grain of rice. While there are many different species of whitefly, they are more prolific in warmer regions where they can survive winter weather.

Symptoms & Identification

Whiteflies are active during the daytime and scatter when disturbed, making them easier to spot than some other plant pests. However, the most common sign of a whitefly infestation is a sticky residue called honeydew the bugs produce when feeding.

In addition to the sticky honeydew, you might find whiteflies themselves on the underside of leaves, particularly along the veins. They also lay eggs underneath the leaves and tend to target tender, new growth on foliage plants.

Treatment & Prevention

While whiteflies can cause trouble in your garden, there are steps you can take to treat an infestation and prevent new ones from happening. Here are some ways you can rid your plants of whiteflies:

  • Hose them off - Washing the insects away with a stream of water is an efficient way to get rid of them quickly. If you find them on houseplants, take them outside for a bath with the hose.
  • Treat with insecticidal soap - Once you've washed the plant with water, use either store-bought insecticidal soap or a homemade mixture of dish soap and water. Spray the leaves and stems of the plant thoroughly.
  • Trap the survivors - Unfortunately, pests usually take more than one round of treatment to eradicate. To help capture and remove any remaining adult whiteflies, use sticky traps in your garden or potted plants.

These are just the basics of dealing with whiteflies. As with all plant pests, the best way to prevent them is to carefully inspect every new plant you buy. With the right knowledge and vigilance, you can keep your garden safe and healthy.