You can prune off or deadhead spent flowers as you wish :-) Just avoid taking back very far....just under the flower head or to the first set of leaf axils.

Thanks gardengal48 for the reply.

No harm will come if you deadhead now. I let Mother Nature do it for me though.

If not familiar with deadheading, see REMOVING OLD BLOOMS under Method One In this Link:

http://hydrangeashydrangeas.com/pruning.html

I did the trim and they look great. The leaves are starting to turn a bit. Once they develop their full fall colour it is going to be really great.

my oakleaf "Pee Wee" flowers look worse than I remember other years. Maybe ample rain we had this summer. I was just considering the pruners this afternoon. Interestingly, the other oakleafs' flowers are not as nasty looking.

Oh, don't tell me that. This has been the 4th rainiest summer down here.

.....but the other hydrangea's flowers are pinking up fine......

Besides, I don't remember Pee Wee's flowers being particularly attractive over a long period of time. Are other peoples'? The best extended color is with my paniculatas and the couple macs I can grow: T & S, Lady in Red. Haven't seen Blue Billow bloom in a couple of years, so I can't even remember it's late season color. When it does bloom the blue is so lovely the plant doesn't owe me a thing by September. I'm happy with what I had during summer.

Marie, I have a Blue billow 20yrs.....blooms every yr never pruned or winter pro. very large 4'x10'

Pretty!Where in Boston area are you? I might have trimmed off the buds by accident this spring. I've decided not to prune back anything except my Annabells. I've made too many mistakes pruning what looked like deadwood and wasn't. I have an oakleaf that is pushing leaves right now out of branches I thought were dead but never got around to pruning. In other words they looked like sticks for 4 months then produced leaves at the tips.

Did the trim a few weeks ago and things look very fine now. The burgundy is beginning on the leaves and things look set for a good fall display