I've had my plumeria for 3 years, and it bloomed last year for the first time. I keep it in a sunny, almost-cold room and don't water it much over the winter, and it stays dormant until the weather starts to warm up. Then it goes into the brightest southern-exposure window I have and gets watered and fed fairly vigorously. I use a bloom-booster feed on it at least once a week. As soon as nighttime temps stay reliably around 50 or over, it gets to go outside on my southern-facing porch. Even then, it blooms late in the season, and I have to bring it into the house in the fall with blooms still on it so the frost doesn't kill it. It's not an easy plant for a New Englander to grow. Maybe this year I'll try the heating mat and artificial lights...or maybe I'm just going to be lazy and suffer with the late bloom time.