I am a fan of both species. Caryopteris Dark Knight bloomed pretty much all summer here its first year. And perovskia bloomed for the last half. Both still have flowers. They seem to survive without much coddling and they look good in and out of bloom. I would offer to take some, but I seriously doubt my own ability to nurture them to the point where they will be safe on their own outside.
Caryopteris can look great with pink roses. It can look even better with yellow and white roses. I've planted perovskia behind dark blue and white iris.
