I hadn't even thought of thrips but I didn't see any in the bloom.

I have that too!! But I don’t see thrips either

I think it is calcium deficiency (could be relative due to soil pH, other minerals or rain) and it can happen with other plants. I read that even periods of transient Ca deficiency when the leaves are growing will warp the leaves. Once crinkled like that, those leaves can't be corrected. Maybe try some gypsum or dolomitic lime depending on whether your roots like acid or alkaline or if you are getting tons of acid rain.

Suncoast, I have medallion too. Watch for the rain Bec medallon is so prone to BS. I been spraying so far so good. But the rose springs back fast and grow new leaves rather quickly. The bad ones I just peel off.

Jin

Thank you Totoro! I'll try adding Calcium. My soil is sandy and alkaline, but I added a lot of OM so it may be bound up.

Jin - Thank you for the caution! I put mine on the back of the Summer Rose Hedge and in full sun in the hopes that it will get enough air circulation and time to dry. I hope that helps with potential BS. I'll keep a very close eye on it.