I Have Whiteflies on My Lantana

Identification

• Whiteflies are small, winged insects that measure 1/16 to 1/10 inches in length. These insects are shaped like a wedge and hold their wings in a tent position. Whiteflies are covered with a powdery coating of wax and often swarm when infested plants are disturbed. Whiteflies often attack lantana, as well as fuschia, crape myrtle, petunia, coleus, bearded iris, canna lilies, tomato, ligustrum, chinaberry, citrus, gardenia, viburnum, persimmon and a variety of annuals. Greenhouse whiteflies and silverleaf whiteflies are both common species of whiteflies that infest lantana.
  
  

Effects

• Whiteflies feed on the foliage of host plants with sucking mouthparts. These insects puncture plant leaves and remove plant sap. Lantana often have stippled or speckled leaves after whitefly feeding and whiteflies can often be spotted on the undersides of plant leaves. Whiteflies excrete a sugary liquid after feeding on plant sap, which is called honeydew. Honeydew sticks to the leaves and flowers of lantana, causing a black crusty coating of sooty mold fungi to adhere to it. Sooty mold is not harmful to host plants, but is an unsightly condition.
  
  

Natural Control

• Whiteflies are highly susceptible to control by natural predatory insects, such as parasitic wasps. These insects do not attack adult whiteflies, but the immature nymphs. According to the University of Florida IFAS Extension, some species of whiteflies are attacked and controlled by fungi as well.
  
  

Chemical Control

• Chemical control products are often necessary when whiteflies are severe. Insecticidal soaps are available at your local garden center and may reduce the population of whiteflies. Horticultural oils can also control whiteflies on your lantana. Both of these products work on contact with the insect, so be sure to apply them to your lantana thoroughly for best results. Horticultural oils also help loosen and remove sooty mold fungi. Stronger insecticides with the active ingredients bifenthrin or carbaryl may be required for heavy infestations. With any insecticidal product, you may wish to test for damage to your lantana by applying it to a small portion of the plant before applying it all over. If no adverse effects are evident after seven days, it is safe to apply to the entire plant.