I draw the line at nighttime lows in the 40's. When my nights/early morning lows stay at or above 50F, my plumeria go out. I don't worry that I will have a morning or two with temperatures in the mid to upper 40's, so long as the vast majority of lows stay above that 50F mark. When the lows stay at or above 60 and the highs are in the 80's, my plumeria really take off. The hotter the better. I would not even think of rooting my cuttings until the temperatures are no lower than 60F and the highs no lower than 80F. Again, I am talking about the 90% of daytime/nighttime temperatures. I am certainly not in MA but I am in a temperate growing area in MS.
