Brussel Sprout Plants Winter Survival?

So I'm reading that Brussel Sprout plants are biennial, getting seed requires them to survive through winter.

But thus far nobody online seems to actually quantify what temperatures these plants can endure unprotected in order to survive and reproduce the following year.

Any advice would be greatly appreciated.

[Yes, I know I can hack a microclimate to protect the plants, but before I invest that effort I want to know exactly what I need to protect them from.]

Most of the cabbage family can tolerate a good bit of frost. In the UK, sprouts are grown as a winter crop and it's perfectly normal to pick them with frost on. In zone 7, I'd be inclined to just experiment and let them grow out. I bet most of them will do just fine!

Brussels sprouts can tolerate hard frost (32F) but may be damaged at temps below 25F according to this article: https://www.botanicalinterests.com/articles/view/26/Frost-Tolerance-of-Vegetables

This article says Brussels can stand temps as low as 20F: http://www.harvesttotable.com/2009/01/how_to_grow_brussels_sprouts/

That is exactly the sort of information I was looking for.

Thanks Tyler.

So they're just vulnerable enough to die here unsheltered, but shelter should be sufficient to keep them alive.

I'll see what happens next winter.

EDIT: and of course NOW I casually bump into the information I wanted. Another site says they can survive down to 0F, which means I'm better off experimenting with different varieties and seeing what survives. [Of course nobody lists which varieties are more cold hardy >_<]

I live in southern maine. I did nothing this last year. It was a mild winter and only had a handful of super cold nights. We did have a week of below zeros and single digits and I had two overwinter. It wouldn’t take but a little protection to keep them two years.  I planted them in a pallet. Sounds trailer park but they and the cabbage a absolutely thrived in the pallet. Doesn’t take a lot of soil either. Good luck

Sprouts can make it down to -15C much under that and they start to winter kill here. It's not just temperature though wind and in my experience damp are the main killers, we sometimes get mild winters -5 minimum but kale and sprouts can still die as it's constantly wet and they rot. This year we hit -19C and all but 2 of my kale plants died, my parents in laws sprouts survived but were to damaged to eat/sell. they pulled them out before they flowers but I suspect they would have flowered if allowed to.  All of these temperatures are for unprotected plants standing in open fields with no snow cover.