Please give some suggestions as to how you winter these in a zone 6. If all leave dry up will they recover in spring from the stem?
I've only overwintered these in pots, keeping them frost free and quite dry overwinter. Don't believe they can take much cold, unlike a few other succulents that will do okay outside as long as they stay dry (some agaves for e.g.) If they shrivel up, they might still come back in spring...tho I've never gotten them dry enough to shrivel...are they shriveling after the cold snap, freezing and now thawing? Or have you just kept them totally dry?
I have kept them dry as last year I lost a few to rot after watering (from bottom) .The leaves go white and papery on ones that are not watered. Some that have rotted have left a stalk that I hope may send off new plants in spring?