where it freezes in the winter? I have several cactus plants that have been outdoors all summer and look great, but now that the temperatures are starting to drop into the 40s at night I'm a bit concerned. I know it must get a little chilly in the desert too but I don't want to risk any damage to my plants. Should I bring them in now before there's any chance of a frost or wait til November when the weather becomes more unpredictable?