I have a lovely Wisteria that's growing on a trellis I built for it, above my fence years ago. Well, I'm sure you have guessed it. It is pulling my fence down. I religiously prune when needed throughout the growing season, but about 1/2 of the main thicker branches are off to the side of my trellis, thus pulling it off to the one side.

My ? is how much of the larger branches can be pruned before damaging the plant? I have trimmed many of the smaller diameter branches off, giving me some space to work on and disassemble the trellis and fence to a more sturdier version next to it. If I do cut 1/2 of the branches out, would the original plant be OK. I would guess that it probably would not leaf or flower much until the next year. The whole length is about 25 feet. Thank you in advance for your help with this.