I really don't want to have to winter over my Bougainvillea under lights this year. Can I prune it severely, cut back on watering and keep it somewhere cool but above freezing in a dormant state over the winter?
Yes, but don't let it get as dry as you would a plumeria. The roots must not be allowed to dessicate, the boug does not have the ability to regenerate new roots in the spring. I learned that the hard way :-)
Try to give it a head start and take it out of dormancy around February if possible - they bloom heavily with enough warmth and light in the early spring months.
Thanks for the info. That's one more plant that I won't have to worry about over the winter. I'm trying to let as much as possible go dormant this year. I just don't have the time or energy to keep all this stuff going through the winter.