Wild pasque flowers grow near Denali (Mt. McKinley) in Alaska. That is probably a zone 2 area. Indeed, they do come up through the snow, which is still around Memorial Weekend when we have camped near Denali. I would love to find some of these wild pasque flowers for my garden, which is actually about zone 4 (lately, probably more like zone 3 as we haven't had much snow - that's right, there are places in Alaska that don't get much snow!).