Huldine is a pruning group 3 clematis. Did you do a hard prune earlier? If you did, then you might want to think about replacing the trellis with something larger. A well-established vine can grow to as much as 15-18' even after an early spring hard prune.

You can prune clematis any time you like but it will reduce or even eliminate flowering if you do it now. Since group 3's bloom on the current season's growth, even a light prune will be removing buds.

Okay that's an awesome answer for me. Well, I can't change my trellis because it's cemented right into the ground but next year I'll replace the clematis with one that doesn't grow quite so long. I just leave it as it is this year and spend some time untangling some of that jungle. lol

At least now I know what happens if I did cut it back now which I won't do. I love the flowers! I pruned it about 8" from the ground last fall. Then, sometime around Feb/March I just cleaned up around the base and removed any old dead stems. Gardengal - once again I thank you for your professional advice.