Hydrangea arborescens 'Annabelle' Frost Damage

We had a couple nights down in the 33°-36°F range and ended up with some frost. I covered most of my 'soft' plants, and my newbie plants, but I didn't cover my Annabelle hydrangea that are now the size of small shrubs growing all new wood from being cut to the ground this winter.

 Hydrangea arborescens 'Annabelle' frost damage on leaf

Brown spots on  Hydrangea arborescens 'Annabelle' leaf from frost

Here is what the frost did to them, little brown patches on the leaves where the cells must have burst from being frozen. Kinda reminds me of a bruise, I wonder if it's biologically similar. One of the benefits of obsessively monitoring your plants on a daily basis is that you can determine that new appearances are indeed caused by the frost, and not just a coincidence of something else going on.

I also noticed one of them is kinda runty, it's the same one that I thought the fertilizer company sprayed with broad leaf weed killer, maybe it's just a runt or maybe it's running into a piece of garbage underground or something. Come on little guy!