Overwintering plants in a zone 5 greenhouse is easier said than done. All in all we’ve had a mild winter for Utah. Much less snowfall than usual and even some warm-ish (45 degrees or more) days in December and January. Our first winter in the greenhouse was definitely a learning experience. On non-cloudy days our greenhouse temps were lovely, often 20+ degrees more than the outside temps. The problem becomes harnessing that heat and providing a slow, steady release during the night to ensure that our tender plants don’t freeze completely. We lost a quite a few succulents this winter, but I was pleasantly surprised to find this little succulent had made it through. Hopefully transplanting into some new soil, along with relocation to the sunniest spot will do it some good.
Next Year’s To Do List for Winter Greenhouse Success
- Cover greenhouse air vents with batting insulation
- Use silicone caulk to seal up loose panels and reduce cold air infiltration
- Increase the number of black water jugs for overnight thermal mass heating
- Look into paraffin wax heaters and solar power options for space heaters