Whiteflies and tiny sap-sucking insects may become common in vegetable and ornamental gardens, particularly in warm weather. They make foliage yellow or die. This blog post will discuss the symptoms and causes of whitefly infestations and various management methods. Cultural methods such as regular plant maintenance and choosing resistant plant varieties can help prevent whitefly infestations.
Biological control methods like introducing natural predators such as ladybugs or parasitic wasps can also be effective. Chemical and organic insecticides can also be used for management. Combining these methods allows you to effectively manage whiteflies in your home garden and keep your plants healthy and thriving.
How to Manage Whitefly in Home Garden
What is Whitefly?
Whiteflies are not true flies but are small, soft-bodied insects closely related to aphids, mealybugs, and scale. They have a triangular shape and measure about 1/12 of an inch. They are usually found in groups on the undersides of leaves. Some of the most problematic species affect many plants, such as the greenhouse whitefly, banded winged Whitefly, giant Whitefly, cabbage whitefly, citrus Whitefly, and Silverleaf whitefly. The Silverleaf whitefly, found in the southern United States, is particularly damaging as it can turn squash foliage into a silvery color when it infests it. Whiteflies are active during the day and tend to scatter when disturbed.
Lifecycle of Whitefly
- Whiteflies overwinter on the leaves of host plants as young nymphs. In late spring, adult females lay 200-400 eggs in circular clusters on the undersides of upper leaves.
- The eggs hatch in 5-10 days, and the first instar nymphs, known as crawlers, move a short distance from the egg before feeding on the leaf’s underside.
- The remaining nymphal stages (2nd, 3rd, and 4th) do not move. A non-feeding pupal stage follows, and young adults emerge within a week to start the cycle again.
- Whiteflies have many generations per year and develop from egg to adult in approximately 25 days at room temperature. Adults may live for one to two months.
Identification of Whitefly in Home Garden
Whiteflies can be easily identified by their powdery white wings, short antennae, and moth-like appearance. The flattened, oval, and scale-like nymphs settle on the underside of leaves to feed on plant sap using their piercing-sucking mouthparts, creating honeydew. The accumulation of honeydew can lead to fungal diseases, and heavily-fed plants may become weakened, turn yellow or pale, and eventually wilt or die. Ants may also be present, attracted by the sweet honeydew.
Garden Plants which are affected by Whitefly
Whiteflies feed on various plants, including ornamental flowers and warm-season vegetables such as tomatoes, eggplant, peppers, and okra. Other susceptible plants include cucumber, sweet potatoes, squash, citrus trees, and plants in the cabbage family, such as cauliflower, cabbage, and broccoli. They can also attack most common houseplants and ornamental plants, especially those with soft, smooth leaves, such as hibiscus, poinsettia, fuchsia, petunia, and roses. Whiteflies are a major pest that can damage various plants in a home garden.
Symptoms of Whitefly attack on Home Garden
- Yellowing leaves that appear dry or fall off plants
- Sticky leaves covered with black sooty mold caused by honeydew excretion
- Ants are attracted to honeydew, which can interfere with natural predators
- Plant distortion, discoloration, or silvering of leaves caused by feeding by whiteflies on plants.
- Serious losses in some vegetable crops caused by feedi