Frost as you can see by the dark spots on the leaves, bit my Blue Hydrangeas last night. JoAnne sent me a note and said:
"Hi Henry,
I covered my tomatoes and peppers last night. It looks like I may have lost the leaves on about half of them. We'll see if they revive while I am on vacation. If they don't, I will be visiting a greenhouse when I get back. Since the stems don't appear frozen, they may grow new leaves. We'll see.
JoAnne"
If you catch them before the sun hits them in the morning, you can use a sprinkler can or hose and rinse the frost off, that has worked for me a number of times.
Bet there are a few tender flowers in the cemetery that got bit also.