Beginner Gardening: Help with seemingly diseased peony!, 1 by wishfulgarden

wishfulgarden wrote:
I'm sad to say, but it seems like there's something wrong with one of my peonies. It has light brown splotches on its leaves. We had a stretch of extremely wet weather followed by some significant heat (around 100 degrees), so maybe that's the cause of it. I'm hoping someone can help me ID the issue and suggest some solutions. This peony is surrounded by a lot of other peonies, so if it's a contagious disease I need to nip it in the bud.

Attached are some photos. Thanks so much for the help!