Plumerias Awaken

I hadn't been aware until this season of how many plants are dormant here in the winter. I had thought that if you gave most tropical plants water, they would grow. Not so. Many plants simply didn't grow at all until March (when it got warmer), even though they had plenty of water. This Plumeria started growing leaves and flowers a few weeks ago. It is tapped into out septic system and gets no supplemental water or fertilizer. I took it off the drip system a couple of years ago.