Whiteflies damage a number of crops: verbena, fuchsia, regal geranium, lantana, nicotiana, ageratum and of course poinsettia. Whiteflies, including the sweetpotato whitefly (Bemisia tabaci), are still the primary insect pest of poinsettia, feeding within the vascular system (phloem sieve tubes) and subsequently removing plant fluids.In addition, the nymphs produce or exude honeydew, which is a clear, sticky liquid that serves as a substrate for black sooty mold. Depending on the source of information about the Q Whiteflies are common insect pests of hibiscus, poinsettia, chrysanthemum, and a number of other indoor plants. Out with Whiteflies on Poinsettia August 2015 Greenhouse growers and whiteflies on poinsettia could be compared to children and Santa Claus at Christmas: Each can’t conceivably imagine the season without the other. Whiteflies can be as small as 1/12 of an inch, are somewhat triangular in shape, and are often found in clusters on the undersides of leaves. The recommended control or regulation program combines weekly releases of parasitoids (the species will depend on the whitefly species) with two applications of an insect growth regulator. The other greenhouse operation received plants in April to produce tree poinsettias. In Canada, researchers and growers are experimenting with dipping poinsettia cuttings in soaps, oils and fungal-based biopesticides to kill whiteflies on infested propagated cuttings (see the April 2017 issue of GrowerTalks). Often, growers can successfully control whiteflies … Whiteflies can be difficult pests to manage, especially in greenhouses where they enjoy a high-quality food supply, favorable environmental conditions and minimal protection from natural enemies. Systemic insecticides work fairly well. Citrus, squash, poinsettia, potato, cucumber, grape, tomato and hibiscus are commonly infested. Two growers received poinsettias in the spring from the West Coast. Two main species of whitefly are associated with poinsettias: The greenhouse whitefly (GHWF, Trialeurodes vaporariorum), and the silverleaf whitefly (SLWF, Bemisia argentifolii). Whiteflies are the most important insect pests of poinsettia, and as such they are the main targets of an insect and mite management program. Host plants include more than 250 ornamental and vegetable plants. One shipment came in late March for stock plant production. Most growers probably have heard about a “new” whitefly that has appeared on poinsettia crops in many parts of the United States, called the Q Biotype. Whiteflies are soft-bodied, winged insects closely related to aphids and mealybugs. They are most often noticed when watering or handling a plant. This approach has an advantage, since some Bemisia whiteflies (the Q-biotype) are resistant to most chemical insecticides. Indirect whitefly damage is caused by the large amounts of sticky honeydew secreted during feeding. Two main species of whitefly are associ-ated with poinsettias: The greenhouse white-fly (GHWF, Trialeurodes vaporariorum), and the Whitefly adults are tiny, white, moth-like insects. On Poinsettia: There were some really tough whiteflies in greenhouses in Summer 2013. In southern and coastal states whiteflies are found year-round in outdoor gardens. Poinsettia Poinsettia (Euphorbia pulcherrima) crops are likely to be infested with whiteflies. Despite their name, whiteflies are not a type of fly, though they do have wings and are capable of flying. Identification Silverleaf whitefly feeding has been associated with several plant disorders, including silverleaf of squash, stem blanching and whitening of poinsettia and cruciferous vegetables, and irregular ripening of tomatoes. A: Whiteflies are tenacious, and those masses on the backs of the leaves are eggs. When disturbed, whiteflies flutter about the plant for a short time before returning to the plant. In northern areas year-round infestations are possible only indoors. Greenhouse growers and whiteflies on poinsettia could be compared to children and Santa Claus at Christmas: Each can’t conceivably imagine the season without the other.