I have an 'Endless Summer' hydrangea that is several years old. It's leaves are coming out now, and I noticed these yellowish spots on them....hoping someone can tell me what it is, or what I should do about it. Thanks!
Have you had bouts with powdery mildew before? I wonder if it could be the start of one.
Here is a link that might be useful: Hydrangea Diseases
Thank you luis, that looks like what it is, so I treated it today.