Generally yes do cut off the flowers going to seed to encourage new blooming branches. This is what I do. But this year there is less branching so far, however the plants got extremely large (12 ft.) I am seeing new branches start as soon as the top flowers, and I suspect I will get a good show, although much later this year. I live in Connecticut.

How the heck can I cut off spent fowers up there? LOL

{{gwi:21157}}