Xanthosoma sagittifolia is winter hardy outside in Augusta, GA, but it is not winter hardy for me here in Marietta, SC, although Colocasia esculenta is.

Don't worry, the corms are sold as Melanga at the food stores. If you hack the stems to the ground after they turn to mush, then mulch the corm, they'll prob be just fine. If not, just grab some big corms at the food store for 1 to $2 a lb. and plant in the Spring, or inside in a pot, then outside in the Spring.