Lauw, In my experience I have never seen C. hederifolium form any sort of trunk or stem as you describe. I have always seen the flower and leaf stems go out horizontally for some distance before heading for the surface. In pots, I always get a ring of leaves and flowers around the the edge. In the ground, the effect is like a wreath, with a hole in the middle. Later season leaves sometimes fill this in a bit. On the other hand, C. graecum is one of the types that grows up, not out. In this species, formation of a trunk is to be expected. I have some elderly tubers, nearly 20 years old, with trunks close to three inches long. The root structure on graecum is radically different from hederifolum, with big, thick, possibly contractile roots only on the bottom of the tuber. My biggest difficulty in growing them is to find a pot that is deep enough to handle the tuber (~4" diameter), the floral trunks as described, and six inch long roots that resemble pencils. Usually the roots wind up getting folded over. I recall an article in the Cyclamen Journal that described graecums found in nature with trunks over ten inches long. All perfectly normal! --Roy NW of Boston ----- Original Message ---- Roy, Allthough I am in a much milder climat (we get frost down to -8° 18F) I never put more then 2-3 cm (1") of soil on it. Otherwise the tubesr make a kind of "stem" to get to the surface. If any doubt put a good layer of mulch, compost etc on it