"Ian" expounded:

I only wish I could remember what I did last year. Did I just cut off the
branches, or did I cut it back to the ground? Whatever I did last year
resulted in a beautiful bush come July.

They are very fast growing, but they die back hard in our winters.
You've doing exactly what you should. If you cut them back too early,
for some reason, it's really easy to kill them. Enjoy!

--
Ann, Gardening in zone 6a
Just south of Boston, MA
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