Janet, I usually wait until I see new growth from the bottom. But I've been seeing that for some time now. Really the only thing I have left to cut back is the Turk's Cap and I've put that off cause it's a 4' deep and about 20-25' long bed ;). Lazy.......

Our temps are going to be getting down into the mid 30s at night this week. You might want to wait till that's over if the same is true for you. The point is not to stimulate new growth until chances of a damaging freeze are past.

Hope that helps,
Kristi

I wait until the actual last frost date. I use dead foliage to hold protective mulches in place tho.PJ

Guess it depends on exactly where you are.
Our gardens are already cleaned up, pruned and seeded.
I'm in zone 8b and mom is in zone 9, although we are only an hour and a half apart.
Then again, our last frost date was in mid-February!