As far as I know, you cut them back in early spring, when the forsythia's bloom. I'm still pretty new at this too. I've planted 4 group 2's this year and cut them back. I planted 3 of the same last year, and cut back. The ones that I cut back last year came back beautifully and more vigorous this year! What I still also need to know is, do you only do this the first 3 years and then stop cutting back so much? I think after the first 3 years, you only cut back the deadwood in the spring.

Kentstar, you are correct. You don't need to cut Type II's back every year, just the first few to get them off to a good start.

However, if they become a tangled or scraggly mess that only blooms on top you can cut them back to rejuvenate them even if they are mature.

Extremely cold temps and will probably kill the tops of the vines, so you'll have to prune them.

I accidentally wacked off most of my Crystal Fountain type 2 last year. It was planted in spring last year, and I was trying out a new weeding tool and wacked off all but a 6 inch stub! That was later on the summer, mid to late summer I believe. There was not even a single leaf left! I just kept treating it like it was still fine, and watered like usual. Well, this year it not only came back, but it is doing better than all the rest of my clems! Vigorous, leafy, and much fuller! So, I guess it liked it!

I prune my clems as soon as the snow permits. Preferably when the ground is still frozen so I don't squish. It doesn't always work out like that. Anytime March-April should be fine.

On related subject, I tried something last year with my Else Spath. sometime in summer, it got truly horrible looking and I decided to cut it down and let it get fresh new growth for the remainder of the season. I was willing to forego possible Sept/Oct late bloom. That part was fine.

However, the next spring all the top was dead and I had to cut it down completely. Its a group 2 so I didn't really want to. So bottom line the hardening off time is very important. Similar to shrub pruning in Z5, probably July 4th might be the cutoff date for safe time to allow new growth to harden off for winter.

And did it grow back lush and extra floriferous this year? not really, same as always - okay, not great.

I planted my first clematis last year. It was suggested on this forum that I cut back type 2's and 3's for the first two years, so the plant focuses on root development.

I continue to cut back until the end of July, then I let them grow after July as Wendy mentioned, to let the new growth harden off for winter.

I also deadhead the blooms to prolong the blooming season.

Last year I had nice blooms in August through October.

This year, MOST are noticably fuller, and next year I'm hoping they'll be stunning.

I have them lined along my fence on my driveway, my neighbor has a direct view from her kitchen, when in bloom they are stunning, and that was just first year growth, I can't wait until next year.

You can either wait until early spring to cut back late season's growth, or you can do this during winter months when plants are dormant if you don't want to look at the brown/crispy foliage. I think I cut mine back in late December last year.