Black spots on my Delphiniums
I have been trying to grow delphiniums for a few years now, with very limited success. They are gorgeous the first year, but most of them develop small black spots on the leaves and die off at the end of the season, never to return. The few that survive the first year usually don't survive the second, for the same reason. I have tried spraying with antifungal, but it doesn't seem to stop the problem. What am I dealing with, and how to I get it to stop?