Rhododendron bud blast

Symptoms - Buds fail to open but stay on the bush looking silvery, and later in spring develop black 'bristles'. The buds remain on the plant for two or three years, but don't rot. The 'bristles' are the spore bodies of a fungus which is believed to be introduced by the rhododendron leafhopper laying its eggs in flower buds. Adult leafhoppers occur on the foliage from mid-July until October. They are 8mm long with yellow head and legs, a blue-green thorax, and forewings striped with red.