Answer: It's really difficult to diagnose a plant problem without actually seeing it so I can only offer some usual causes of leaf cupping and suggest you take a sample of the leaves to your local Cooperative Extension office (Smith Bldg. downtown Seattle) or Master Gardener Clinic, or take samples to WSU Plant Pathology Lab in Puyallup. Cupping can be the result of herbicide damage, insufficient water, or a calcium deficiency in the soil. Without knowing precisely what is causing the cupping, I can't suggest anything to help alleviate the problem. Do take a sample in for positive identification and suggested remedies. Best wishes with your shrubs!
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