Answer: It sounds as though your azaleas are suffering from dieback . This is a plant disease caused by several different fungi. The fungi enter the plant and cause cankers that block off the flow of nutrients and water to stems. Once the branches have begun dying back, there is no chemical cure. Just prune out and destroy all affected branches. Sanitize pruners between cuts with rubbing alcohol. As a preventative, you can try spraying with a copper-based fungicide in the spring after blooming, repeating the application again in 2 weeks. Be sure to follow all instructions on the pesticide label. Also check the soil pH to be sure it is acidic (5.0-6.0). If the pH is too high (7.0), the nthe shrubs may not do very well.
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