How do I get rid of fuzzy white stuff on my pyracantha bush?
The Gardener’s Answer
Hello, Fran: All plant material is more susceptible to insect and disease problems when they are not planted in an ideal location. Pyracantha, commonly known as firethorn, belongs to the Rosaceae (Rose) family. They should be planted in a space where they will receive good air circulation and a minimum of six hours of direct sunlight. The first step to a healthier plant is to have the problem diagnosed. I cannot say for certain without being able to see your pyracantha so you should take a sample to a reputable garden center with a knowledgeable staff or to your County Extension Service. Pyracantha is prone to a few different disease and insect problems, but from what you have described it sounds like you might be dealing with wooly apple aphid. The aphids themselves are purplish-brown but they cover themselves in a mass of waxy, white threads. Have you noticed any galls on the bark or a sticky substance that might be attracting ants? If so, an insecticidal soap will help but you should have it looked at before you spray anything on your pyracantha. For now make sure the base of the plant is free of plant debris and remove any severely infected foliage.