A greenhouse that goes into winter clean, tight and properly anchored is easier to heat, safer under snow and ready to go in spring. Here are ten jobs to do before the first real snowfall where you live. Most of them take an afternoon.
Structure
1. Check the base and the anchoring
Walk around the greenhouse. The base should sit flat on its foundation with no gaps, and every anchor point should be tight. If your Harmony, Mythos, Hybrid, Balance or Essence was never anchored, Palram-Canopia's anchoring kit is made for those models. For the base itself, see our fall foundation guide.
2. Tighten what has worked loose
A season of opening doors and vents loosens things. Check bolts, door hinges or tracks and panel clips, and replace anything missing or broken. For replacement parts, use our parts and warranty form.
3. Make sure doors and vents close fully
Gaps let heat out and cold air in. Every door and vent should close and latch properly. If you have an automatic roof vent opener, check that it opens and closes smoothly.
Light and water
4. Clean the panels inside and out
Winter days are short, so every bit of light counts, and dust, pollen and summer grime all cut into it. Wash polycarbonate with mild soap, lukewarm water and a soft cloth or sponge. Skip abrasive pads, scrapers and harsh solvents, which can scratch or cloud the panels.
5. Clear the gutters
If your greenhouse has gutters, clear out leaves and needles so rain and meltwater can drain away instead of overflowing or freezing in place.
6. Drain hoses and drip lines before the first hard frost
Water expands as it freezes and can split hoses, fittings and drip lines. Drain them and put them away before night temperatures drop below 0 °C. If you run one of our drip irrigation kits, drain its lines too.
Heat
7. Test your heater before you need it
Run it on a mild day and make sure the thermostat switches it on and off. Not sure one heater is enough? Our winter heating calculator shows how many hours a day a heater runs, what it costs through the winter and whether one unit will hold your target temperature where you live. The Palram-Canopia fan heater with digital thermostat we carry is rated at 1500 W (5,500 BTU) and has a splash-resistant IPX4 design.
Whatever heater you use, keep it clear of plants and plastics, and plug electric heaters into a GFCI-protected outlet. Propane and kerosene heaters produce carbon monoxide, so follow the maker's ventilation instructions exactly.
8. Hang a thermometer
A min/max thermometer shows you the coldest point of the night, which is the number that matters to your plants.
Snow
9. Know your snow rating, and what it means in real snow
Every greenhouse we sell lists Palram-Canopia's snow load rating on its product page, for example 75 kg/m² (15.4 PSF) for the Mythos and Hybrid and 100 kg/m² (20.5 PSF) for the Glory. A rating is a weight, not a depth, and wet snow weighs far more than dry powder. Our snow load calculator turns your model's rating into a safe snow depth, and our snow density table shows how much different kinds of snow weigh.
10. Plan how you will clear it
Do not wait for the rating: brush heavy snow off after every big storm. Work from the outside with a soft broom or a snow rake with a plastic or foam head, and avoid chipping at ice or pushing up on the panels from inside. Watch for snow sliding off a nearby roof too, since it can dump a lot of weight on a greenhouse at once.
Questions?
Call us at 1-877-322-5487 or email sales@canada-greenhouse-kits.ca. We are a Canadian family business and a certified Palram-Canopia dealer since 2007.