Your right I was thinking it was similar to peyote that's another mescaline containing one but it's much hardier. Either way the rain would kill it here before the frost. Not sure we even had one last winter it just rained continuously.
Discussion
Yes, constant wetness is a sure death. They love getting soaked, but they need to dry out. When dormant, being wet isn't good. I did give mine drips of water last winter, mostly run-off from the tent. The previous winters they looked like they could have used a few light waterings.