I have been having problems with my snowdrift clematis. I planted 3 last year hoping to get beautiful blooms this spring. The buds turned brown/black and some of the leaves have also turned brown or the veins have turned brown. I planted a new one and the new leaves have gotten brown spots on them. From what I have read, it doesn't sound like the clematis wilt. I am not sure if it is just frost damage. I live in Washington state and we have had a frosty spring.