Red tip photinia (Photinia x fraseri) is an evergreen shrub set on fire, showcasing brilliant red new growth that shines atop mature green leaves. Though red tip photinia is more prone to diseases than pests, pest infestations may also occasionally occur. An infestation of white bugs is likely caused by sap-sucking insects such as aphids or lace bugs.
Aphids are generally wingless insects that may be green, yellow, brown, black or red, though they may have a cover of a whitish waxy or substance that makes them appear white. They can often be found on tender new growth, feeding in groups, or on the undersides of leaves. Lace bugs are small insects covered with a lace-like covering of cells that may be whitish or transparent. They also are commonly found on the undersides of leaves.
Large populations of aphids can cause the striking red and green leaves of red tip photinia to turn yellow. An infestation is often present with a sticky residue called honeydew that results in a black, sooty fungus. Aphids may also cause leaves to curl or develop bumps called galls. Lace bugs leave behind stippled patterns on leaves as they drain foliage of plant sap. This damage can become severe by the end of the season as the leaf loses color. Both pests may leave behind specks of dark excrement.
Natural predators will often solve an aphid infestation, according to the Virginia Cooperative Extension, which advises against potentially plant-harming chemical controls. Avoid using broad-spectrum insecticides, which indiscriminately kill beneficial predators and insects. For lace bugs, the University of California Statewide Integrated Pest Management Program recommends applying narrow-range oil or insecticidal soap; or, in mild infestations, allowing natural predators to do their job. For the oil or soap to be effective, the entire plant must be covered, including the undersides of leaves. Follow label recommendations for amount and frequency of application.
A healthy red tip photonia is less like to attract pests: the Virginia Cooperative Extension notes that aphids are attracted to yellowing, sickly plants. Suitable for U.S. Department of Agriculture plant hardiness zones 7 to 9, red tip photinia grows best in a bright, sunny location with well-draining, moderately moist soil. Good air circulation is a must, as this plant is prone to fungal leaf diseases. Prune in the winter to allow air to penetrate the inner branches.