Leaf streak?? I've got that.
This plant is the worst one in the yard. Sprayed it about 3 weeks ago with Garden Safe Fungicide3 to see if it would help and it looks like it might have since the new growth seems to still be a dark green. -LS doesn't seem to effect the blooms and doesn't kill the plants, just makes the foliage look bad.
Just read what Michele wrote about leaf streak working toward the tip... maybe the fungicide didn't work after all, probably not, I've had ls for the last 3 years.. probably not going anywhere...