Answer: Rhodies are subject to many fungal diseases and a few insect pests. What you describe could be the latter stages of a disease, or simply the result of sun scorch. For positive identification of the problem, and control recommendations, take a sample of the affected leaves to your local Cooperative Extension Service or Master Gardener Clinic (usually at Farmer's Mkt's). Helpful folks there can help you solve the problem. Best wishes with the rhodies!
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