Allow the frost to knock them down. Remove from the pot & remove the soil & leave them on garage floor for several days to dry. Store in a bag of dry peat moss for winter in a warm place. They don't like to be stored at temperatures under 70*F. or they will show reduced vigor in the next grow season. Some allow frost to knock down & then store the entire container in a warm dry place w/o water. I have tried both methods & prefer the bag/peat method. Pot them up in late Apr & water lightly. Keep them warm if possible while in containers. They won't do much in the ground until it warms a bit, either. They are very heavy feeders, so don't be shy with the N. I use lawn fertilizer (27-3-3) on them in the ground & Milorganite or 5-1-1 fish emulsion in containers when actively growing. Al

yes! the leaves and tubers. both, are edible as I bought them from the indian store as a vegetable. I did read a long time ago about various types and if I remember, they are several genera( and more species) in this collection? As I do not know too much about the edible factor for them, I stick to the edible ones from the indian store, Colocasia sp. ( maybe esculenta). The green stem and the purple stem. Where did you buy the tubers? You must make sure that they are edible ones. They are some that are ornamental ( the one with the dog picture are ornamental types , I think) As the oxalic acid content is pretty high in the leaves and tubers, you have to cook them really well. In India we cook steam them with brown sugar and Tamarind paste/lime juice along with indian spices to offset the oxalic acid crystals. The can really scratch your throat. My husband will not eat them as he is very sensitive. I do not seem to have too many issues. For that matter , Purslane, and some other greens, have a bit of Oxalic acid crystals. I love Purslane too. I cook them with lentils. Mm mm.

I've never grown these but for most tubers and bulbs the recommendation is a cool, dry place. Maybe a paper bag in the crisper tray? Just be sure it never gets below freezing. Of course, if you've got an unheated cellar that doesn't freeze,you are well ahead - just make sure they are protected from mice since the tubers are very edible. Also a good idea to check mid-way through the winter and, if they show signs of shriveling, dampen and put in plastic bag to rehydrate. Or store in damp sand.

probably is the species c. esculenta. it should not be hardy for you outdoors in zone 7a but may persist for some years until temps go low enought to kill it. they like moisture and shade but will take sun if the soil is not allowed to become dry for extended periods. plant the top of the tuber at or just below soil level. i am growing a cultivar with smaller blackish foliage in a large plastic planter. i did not knock out the pre-punched drainage hole in the bottom so i can keep the soil saturated and they seem happy there in a half-day of sun. in your zone, container-grown plants would need to be overwintered in a protected area or dig the tubers and hold them over the winter in a cool, dry area.