Answer: Based on your description, there are several possible reasons the rhododendrons are failing. Among the most common would be a disease or fungal infection, insect acitivity for example unseen and feeding on the roots, or even the cumulative effects of long term stress such as encircling roots or poor drainage finally taking their toll. You might want to consult with your county extension (431-7260) without delay to see if they can help you determine the specific reason for the change and suggest what to do. I'm sorry I can't be more helpful.
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