Help, my roses all seem to get black spot! The leaves start to discolor, turn yellow with black spots, then fall off. The new leaves appear and in a few days, the same. I have treated with sprays and granular fungicides. I cannot stop or hault the problem.
I live in Southern Indiana. It is HOT and HUMID! 90 degrees and upper 90's% humidity. If I need to post more info, tell me what I need to post and I will.