I am just new to the forum and to dahlias. All my 10 tubers grew, but only a few bloomed. Now in late September the leaves have developed a problem. It starts with the tip of the leaf turning gray/black and then it progresses up the sides of the leaves and then to the rest of the leaf, until it dies. It looks as if someone burned, singed the leaf. I looked for diseases called scorch, etc. but they didn't seem to fit. Does anyone know if this is a disease or a condition? I sprayed some with fungacide and there doesn't seem to be a difference in reactions of the sprayed and the non-sprayed. Thank you, Karen Shaver (Liebran--hobby kennel, raise purebred Irish Water Spaniels)