Lisa, if your garage was unheated it got about the same temperature as the outside temps. Four years ago I overwintered several dozen plumeria in my unheated garage, no cuttings, all rooted and in pots. We had several days of very unusually low temperatures, down into the low teens, but the biggest problem was that we did not get above freezing for three days. I lost every single plumeria in the garage. I learned my lesson.
