Answer: It sounds like fungal leaf blight (Botrytis). Look for grayish black spots that expand and eventually form a dead mat on the leaf. On flowers, the buds will rot before opening. During wet weather, botrytis blight spores are released and attack the leaves and flower buds of many plants. The best control is to space plants farther apart for better air circulation. Water only in the morning - so water isn't sitting on the foliage at night - and clip off infected flower buds as they form. You may sacrifice flowers for a week or so, but when the weather gets drier, new flower buds will form. In fall remove all dead plant debris - where botrytis fungus overwinters.
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