I"m in zone 9b, I have red and purple, the purple is much more cold hardy, I do have oak trees overhead, they have not ever frosted to the ground, and we have gone below freezing a few times since I've had them, even a few hours upper 20's on the rare occasion, might get a bit droopy, but perk back up. The red is pretty hardy, but mine is in more open area, and has been damaged, by frost, but does come back. Seems the red is more a summer/fall bloomer and the purple is more winter/spring bloomer in my garden. Hummers love them both. In the late spring my purple is done blooming, so i hack it back, both are very easy to propagate from stem cuttings.
This pic was taken in the end of Feb. after a pretty cold winter a few years back, you can see the freeze burn on the Schefflera in the back of it. By the way, I ended up digging this whole plant up and moving it to another spot in the garden since it got too big for where it was, did just fine.
