Eric,
I saw brass monkeys heading for warm caves last evening.
It got down to 16 but my GH stayed at no less than 58 with the kerosene heater set as low I could get it to go. Currently, it is 26 outside and 59 inside but I am running only a couple of heaters: one 450 watt and another that is 1200 watts. But what surprises me is that they are running off a 15 amp breaker.
C21H30O2 - Here's a pic of the plants upstairs.
The Apple is on the left, the basjoo on the right.
Mike