A clarification. There are many, many different types of dens. However, they seem to fall into two classifications of culture and care: monsoonal and non monsoonal. The den-phal types (non monsoonal) which need to be kept warm and moist then dry out during the winter and the den-nobile (monsoonal) types which need to be cold and dry all winter. And the den-nobiles do not necessarily bloom on leafless canes. Some canes stay evergreen for a while. Mine is blooming now on a heavily leafed cane, and it will probably lose those leaves next fall or winter. They do, however, bloom on old canes. Dens do not like a lot of nitrogen.