My Rose bush leaves have white spots on them with holes in the leaves. What is causing this, and how can it be fixed?
Rose Bush Leaves
Certified GKH Gardening Expert
The white spots could be powdery mildew, unless the white spots also have the holes in them. Then it is likely an insect problem or perhaps even a caterpillar problem. For powdery mildew, check out this article: https://www.gardeningknowhow.com/ornamental/flowers/roses/roses-powdery-mildew.htm .
Also, there is a great site to check out of finding out what insect or caterpillar might be making those holes in the leaves here: http://www.sactorose.org/rosebug/
To control the insect or caterpillar problems, a product called Sevin or one by Safer, called BioNeem is good.