I prune these back to ground level too.Their deep rooted and we hardly ever have a hard freeze.LOL but we did have snow this winter.Still didn't hurt them though.My brug looks about like yours Spider. Antoinio pruned it to the ground. I am so grateful it survived. All three of my bleeding heart vines died and I paid a pretty penny for one of them. Oh well. I will replace one of them and keep it in the house this winter.