Question From: J. McKinney - Piedmont, Oklahoma, United States
Q: The leaves of my Double Knockout roses are getting a white build up around the leaf edges. Not observed anywhere else on the plant. Powdery Mildew Fungus and pictures of Scale don't look like this problem.When the white is scraped off. that portion of the leaf is missing and brown at the edge of where the white build up was. Your help will be appreciated. They don't look like pictures of Powdery Mildew or Scale?
Take cuttings into your local independent garden center for a more accurate diagnosis. Best And Happy Yardening, Nancy