Jaime - when I germinated D. canariensis several years ago, I didn't give it any special treatment, other than (probably) soaking the seeds in water for 1-2 days prior to sowing. It germinates and grows easily at 60-70 F. I found it to be vigorous - it send off all sorts of stolons that form outlying tubers - and not at all resistant to freezing (melts pretty fast). Ellen Hornig