Aloe comosa is a silver-blue tree aloe that comes from the NW part of South Africa. Huge specimens can be found near the spillway of Clanwilliam Dam. This area is a winter rainfall area but these plants dont seem to mind and really enjoy the water whenever its warm. My plants took 12F without any signs of damage and it even kept growing without issues. They really seem to grow in cycles, it will sit idle for a month then grow 5 inches. Might be a good candidate to try in zone 7s if you are are the dryish side in winter.