[Koala Doug]

I use an old heating pad from the '60s... it doesn't shut off automatically and it was already sitting unused in the closet.


The only issue is the lowest temperature is too hot to be used without some sort of a barrier between the pad and the seeds. I just put a few towels on top of it, monitor the temperature with my Thermopen (instant read cooking thermometer), and adjust the amount of towels as necessary.