Wilting autumn joy sedum
We have four autumn joy sedum that have been in the ground two years. They've looked wonderful up until a month ago. One of them started looking very very wilted then. Now all four are wilted, only a few stems are even completely upright. They're on drip, and the ground seems damp enough. A friend who owns a nursery came by, and said she'd never seen anything like it, AJS is an invincible plant in our area. Can you give me any ideas as to what it might be? Thank you very much.