Dave, I live in zone 5B and our winters are much too cold to overwinter elephant ears and sweet potato vines outside. I always dig mine up, wait a few days for the leaves to die back and then I cut them off and place them in a soilless mix and in a cool but dry place in my basement. It has always worked for me. These are tender bulbs or so they appear to be, I don't think they would overwinter well outside due to the heavy cold temps we get............Wayne

My previous post was directed at overwintering bulbs, I wouldn't want to wait untill a hard freeze hits for fear of loosing my bulbs.............Wayne

Thanks for your replies. I was planning to bring the bulbs in after a hard frost. I have always just dug the plants up and cut off the tubers, dry them and then store in peat most inside. I also fear that I might lose them if I waited for a frost