Notches from the outer leaf edges and inward usually signal weevil damage. I'm seeing some of that, but the holes that begin within the leaf and not from the edge would make me suspect caterpillar of some kind. Go out after dark with a flashlight and look. If caterpillar, it could be just one and you could quickly dispatch that. I use a pair of beat up old hand pruners ;) Pick up and stomp works too.

It doesn't look urgent to me. If it doesn't become worse, I might be tempted to just removed the ragged leaves individually, tidy up the look if in a prominent site.

I have a large potted rhododendron on my patio. I was cleaning up a handful of partially eaten leaves one afternoon last week and darned if I didn't find the caterpillar. I couldn't identify, some kind of 'inch worm' type. It's gone. No more bites.

Unrelated to your question but I’m curious about the purple blue hydrangea flowers peeking on the side. Is that plant in a container? I just got one (from Home Depot) it has pink blooms that I’m trying to get to blue over time but I want to make sure the plant establishes itself first - any tips are most welcome! Eg type of pot, size, sunlight

I overwintered outdoors in a mini-plastic green house on my north/NW facing balcony that gets no sun during the winter. It was and still is in a 10" hanging basket (about 2 gallon). I potted it in a chunky bark mix (fine pine bark/peat moss/perlite somewhere in the range 5/1/1 to 3/1/1, I don't recall anymore the exact ratio I used). It got some direct sun early in the season but lives in the shade since it started blooming. I will likely pot it up in a 3 gallon pot this fall. A second one that I had in normal potting mix died over the winter so I think a very well draining mix and protection from rain/snow is probably important for its winter survival outdoors.

Thank you. Yeah protection against rain and snow will be tough. I like the green house idea. I’ll look into that