On top of being late this year, I have this going on. Several of the clusters have also gone bad with tiny black spots. Any ideas what's going on? First the leaves go all wilty and then the black around the edges start. Merlot Vines
Your in WA State near Seattle right? You guys have had rain nonstop this entire Spring. I would suspect some type of fungal disease. Perhaps black rot. Have you been spraying?