Peony Problem

Peony Problem

*waves* I mostly lurk in this community and get inspiration for my garden, but I have a problem I could use some help with. I moved into a new house late last summer, so this is the first full season in my garden for me. (I'm also very new to this gardening thing, but so far I enjoy it!) I inherited several peony bushes, 1 which is doing fantastic! Another is "eh", and the third...well, it's sick. I think from looking online it has Powedery Mildew? You can brush it off the leaves, but of course it comes back. It's only on the one bush, and I don't want it to spread to anything else in the garden. Can you take a look and try to diagnose the disease for me please? Also, are there any natural (ie safe for pregnant women) remedies I can try? The 2 healthy ones...I can't figure out why one is big and lush and the other is a bit wimpy title or description title or description title or description Thank you in advance for all your help!
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My landlords didn’t work out

City flowers

City flowers

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hello and new

Thunder Bay Horticultural Society Annual Flower, Fruit and Vegetable Show

Thunder Bay Horticultural Society Annual Flower, Fruit and Vegetable Show

Today a caterpillar, in a few weeks, a monarch butterfly

Today a caterpillar, in a few weeks, a monarch butterfly

ID help

ID help