Cautionary tale to any of you keeping hobby greenhouses throughout the winter. I relied on a single heat source to keep my greenhouse warm. Welp, it got into the teens last night, and my heater failed around 10pm after I was already asleep. I got the alarm, but didn't notice until the morning. My pineapples, tropical plants, and potted vegetable crops are all toast. Some of these plants I've had for almost 20 years.
Have a backup heater in case your main source fails. It'll save you a lot of heart break.
by Optimoprimo