I'm in zone 6a and I've had snaps survive mild winters...
they are one of the few I start inside, because they do really great started from seed and moved in ground before last frost to give me the garden fix I jones in March.
The plural of anecdote is not data.
The plural of bozos is Dasilyl - so please don't engage with my website troll who typically caches my first post and responds ugly just to be nasty. If it gets upity, please ignore it.