I think most here would tell you, for your zone, that you'd have better success with a wider range of brugs if you tried overwintering in the ground instead of a pot.

I'm sure you'll hear of some others that have a better chance at surviving a prolonged winter freeze but I'd vote for Charles Grimaldi as the cold hardiest, but it's roots can grow as thick as it's branches and would threaten the pot that they are in. And it does have serrated leaves, like a bread knife's edge. As it is an offspring of Dr.Seuss and Frosty Pink, you might be able to find someone with a CGrimaldi without the serrated leaves. Anyway, that is a difficult find to acquire and your pot would still have to be tough enough...lol

Frosty Pink is also known as cold hardy but like most brugs probably wouldn't tolerate a potted condition in a freeze but maybe in your zone with some added protection...maybe.

I'm currently under the impression that if the brug is a big size the greater chance it's bigger roots will survive a freeze and that's probably the one factor to consider what 'cold hardy' means and not any subspecies in general...until we find out different. I am NOT saying that any brug can survive a freeze in a potted condition, this is not for me to say, never saw it or heard of it.

For others who have had a brug survive a freeze or two, probably in the ground in their zone, I doubt they considered how long the freeze lasted. There's a difference between 1/2 hour and a few hours!

You have a good question, but there's going to be varied experiences even if it were possible with certain brugs, maybe someone lost there's because they didn't give it a little drink of water during a prolonged dry spell which could happen and they wouldn't necessarily know that's why they lost it.

I lose plants in spring due to this. So now I know, never 2 weeks without snow, rain or water in the spring.

Anyway, maybe you'll have someone come in that has had success with particular brugs, we do have some gamblers who try it on some brugs but they tend to have so many brugs it kinda helps to be brave enough to do such an experiment...lol. One thing is for sure, you won't get a guarantee of survival from anybody just perhaps a good chance.

So what brug did you have that you lost this way?

- Sandy