On 14 Dec 05 at 0:21, Johannes-Ulrich Urban wrote: > I also have made the experience that some Tropaeolum tubers just do not sprout > although they are firm and healthy. I had this experience with Beauverdia sellowiana (Ipheion sellowianum, now yet some other genus) after it over-wintered in a cold frame. The tubers were firm and sound but no growth for several years. I eventually concluded that the cold spell it had undergone had induced dormancy that could only be broken by warmth, so brought the pot into the house one spring and kept it warmer than usual. And, yes, the bulbs started to grow again, to my pleasure. Deep dormancy has to be viewed from an evolutionary perspective: it allows the plant to survive a long period of unfavorable conditions. The trick is to successfully guess what the unfavorable condition is: too cold? too hot? too dry? and then persuade the bulb that good times are back. -- Rodger Whitlock Victoria, British Columbia, Canada Maritime Zone 8, a cool Mediterranean climate on beautiful Vancouver Island