I only had it on one plant (newly planted this year). The spray stopped it dead in its tracks. Mind you, it was in its very early stages when I tackled it. All my other established ones are green and healthy, even though it has been so hot and humid. Thank goodness for peonies and daylilies being fairly drought resistant!
I have two phlox that are fairly mildew free, but this old cultivar is not. I believe the old one is Blue Boy.
Thanks for the tip about pruning them back. Does it make a difference that I am north of you, so my plants start growing later?
