So according to Weatherunderground, it's currently 9 out. Not 29, not 19... Nine. According to my thermostat, the sensor outside is 14 degrees. Granted, this is an unusually cold winter apparently, but, yeah, kinda kills the Filiformis idea, I think.
It's probably too late to save them, but should I consider bringing in the smaller pots (VFT and my "ressurected" S. Purpurpea) and putting them in the fridge for winter?