Hi, I have the same problem as Uli. Mine often don't come up. Sometimes when I've looked later they are gone but other times the tubers look just fine. If they don't come up, do you still keep watering them every now and then. The worst one for me too is T. brachyceras. T. tricolor is the easiest one from me. I grow it outside, usually in a pot submerged in the ground. Last year I just left it there all summer and it came back just fine and seems to tolerate our very wet winters. Still, I think when they first shoot out they are all very fragile. Mary Sue