Update:
Well, it's about to get down in the 20's(F) again. This time I took some precautions to hopefully save some electric and plant growth. I caulked and taped out air leaks. Applied bubble wrap for insulation on shutter. Put in a black barrel full of water for passive solar heating. Hopefully it will soak up heat during the day and release during cold nights. Covered remaining plants with sheets and put in a light for heat [couldn't find another heater-sold out].
Air leakage area...
Black Barrel Full of water for heat...
Grow light for additional warmth and hopefully happy little plants...
This one is starting to regrow...
