Whitefly Control & Treatment

How to Get Rid of Whiteflies

Since whiteflies can be so difficult to control, combining cultural, biological, and chemical methods for the optimal level of whitefly treatment. With an infestation, you will want to know how to kill whiteflies, and using parts of all of these methods will help you do that.

Cultural Control:

• If possible, remove infested plants from your garden or greenhouse. You can treat these plants in isolation or get rid of them.
• If caught early, you can employ a rigorous routine of hand picking the nymphs and eggs, vacuuming live flies, and hosing or spraying plants down with water a few times a day.
• You can vacuum live adults early in the morning with a small handheld vacuum. Freeze the vacuum bag overnight to kill insects.
• Reflective mulch or tinfoil can repel whiteflies
• Create traps by painting strips of cardboard or wood bright yellow (to attract the flies) and coat with a sticky substance, whether it is petroleum jelly and mineral oil or a commercially available product. Rinse trapped insects off, and reapply the substance. You can also purchase sticky traps.

Biological Control:

• Dusty conditions, ants (feeding on the honeydew), and insecticides all interrupt the natural enemies feeding on the whiteflies. Try to control these three things to help keep your whitefly population down before it gets out of control.

Chemical Control:

• Since many species of whiteflies have developed resistance to some chemicals, it is difficult to know which products will work in your area for whitefly pest control. You can try neem oil or insecticidal soap as a first attempt.

• When using neem oil or insecticidal soap, the spray will directly affect live adult flies and feeding nymphs and can also smother eggs or non-feeding nymphs. Coat leaves with oil completely and ensure it is not too hot for these products – read all instructions before using any pesticides.

Whitefly Identification and Life Cycle

Whiteflies are tiny, sap-sucking insects frequently found on vegetable plants and ornamental plants. Like aphids, they excrete a sticky “honeydew” substance that attracts ants. Adult whiteflies are very small, 1//10 to 1/16th of an inch long. They look like small, white moths with a powdery wax covering their wings. Females lay 200 to 400 eggs. These insects go through four nymphal stages. The first stage is called the “crawler” stage, as you will see these tiny whiteflies on plants, moving slowly across leaves to feed. In the final stage before adulthood, the nymphs lose their wings and legs and attach themselves to leaves with wax protrusions.

Whitefly Damage

Whiteflies have a wide range of hosts. When whiteflies infest plants in large populations, they can turn leaves yellow and dry and cause leaves to drop off. Some species cause distortion, silvering, and discoloration, and can cause serious losses. The honeydew secretions serve as a growing medium for sooty black mold, which can be damaging. Low levels of these pests don’t cause significant damage, and fruit trees are usually unaffected. Some species in certain areas of the country can transmit plant pathogens. Often times whiteflies become a problem when the natural enemies of whiteflies – lacewings, big eyed bugs, minute pirate bugs, some lady beetles and some Asian beetles – get disrupted.