Garden Pests and Diseases: Lilac leaves are cupping, 1 by roswellmartian

roswellmartian wrote:
The lilac bush I am writing about was a wedding gift to my mother from her uncle who has passed away, and is cherished by her. I can't replace it or cut it down and regrow as she is very elderly.

The bush bloomed beautifully this year. Then the leaves on some areas of the bush began cupping, then drying up. This has not affected the entire bush, at least not yet. Last year I had some leaf problems too. Some areas turned black and fell off. Those same areas did not produce leaves this year, but do appear to have buds on them that have not opened.

I don't know what to do about this. Is the wood itself infected? Any help would be appreciated. Thanks.