The best greenhouse for a Canadian winter has rigid polycarbonate panels, a frame you can anchor before freeze-up and a roof you can keep clear of snow. We compared five of the best cold-ready greenhouses at Aosom Canada to show which one suits your climate and yard.
Quick Comparison: Which Greenhouse Handles Canadian Winters Best?
All five picks use rigid polycarbonate panels, which hold heat and block wind far better than plastic film.
| No. | Greenhouse | Best Winter Use | Rating | Price |
| 1 | Outsunny 6.2′ x 8.3′ Polycarbonate Greenhouse [1] | Snow and wind, 8 lbs/ft² roof load | 4.6 stars, 41 ratings | $429.99 |
| 2 | WWC 8′ x 6′ Double Door Greenhouse [2] | Cold winters down to -20°C | 4.5 stars, 58 ratings | $771.99 |
| 3 | Outsunny 8.2′ x 6.2′ Greenhouse with Temperature-Controlled Window [3] | Self-venting, built-in raised beds | 4.6 stars, 60 ratings | $584.99 |
| 4 | Outsunny 16′ x 8′ Walk-in Greenhouse [4] | Family vegetables into late fall | 4.6 stars, 16 ratings | $859.99 |
| 5 | Outsunny 6′ x 4′ Lean-to Greenhouse [5] | Small yards, sheltered house walls | 4.7 stars, 39 ratings | $294.99 |
Note: All prices are in Canadian dollars and correct at time of writing. Confirm price and stock before ordering.
Our 5 Greenhouse Picks for Cold Canadian Climates
Each pick below is matched to a specific Canadian winter need, from heavy snow and wind to small yards.
1. Best for Snow and Wind: Outsunny 6.2′ × 8.3′ Greenhouse [1]
| Specification | Details |
| Price | $429.99 |
| Overall Size | 74.8″ W x 99.2″ D x 79.1″ H |
| Frame and Cover | Aluminum alloy, 4 mm polycarbonate |
| Anchoring | Galvanized base, no stakes or bolts included |
| Cold and Snow Note | 8 lbs/ft² roof load, Windproof Level 6, not built for heavy snow |
| Customer Rating | 4.6 stars, 41 ratings |
The Outsunny 6.2′ x 8.3′ Polycarbonate Greenhouse is the only pick with a stated roof load, 8 lbs/ft², along with the highest wind rating of the five. It is also the top-selling greenhouse at Aosom Canada. At $429.99, it gives you about 52 sq ft of rigid growing space.
Pros:
- Rooftop vent: Releases humidity on sunny winter days.
- Rain gutters: Collect rainwater instead of letting it freeze at the base.
- Single-hand sliding door: Easy to open with a tray in your other hand.
Cons:
- Anchors sold separately: Buy ground anchors or bolts before the ground freezes.
Best For: Gardeners in snowy, windy areas who want the strongest stated specs at a mid-range price.
2. Best for -20°C Winters: WWC 8′ × 6′ Greenhouse [2]
| Specification | Details |
| Price | $771.99 |
| Overall Size | 94.5″ L x 74″ W x 89.5″ H |
| Frame and Cover | Aluminum alloy, 4 mm polycarbonate |
| Anchoring | Galvanized base, no stakes or bolts listed |
| Cold and Snow Note | Rated -20°C to 70°C, no snow load listed |
| Customer Rating | 4.5 stars, 58 ratings |
The WWC 8′ x 6′ Double Door Greenhouse is the only pick with a stated cold rating, down to -20°C. Its panels let in 70% of light and block over 99.9% of UV, which helps during short December days. The 89.5″ peak is the tallest of the five.
Pros:
- High light transmission: 70% makes the most of short winter days.
- Two sliding doors: Quick access without leaving the greenhouse open for long.
- Drainage gutter: Meltwater runs off instead of pooling on the panels.
Cons:
- Highest cost per square foot: About $15.90, nearly 2.5 times the 16′ x 8′.
Best For: Gardeners who want a greenhouse with a stated -20°C cold rating.
3. Best for Automatic Ventilation: Outsunny 8.2′ × 6.2′ Greenhouse [3]
| Specification | Details |
| Price | $584.99 |
| Overall Size | 98.4″ L x 74.8″ W x 86.2″ H |
| Frame and Cover | Powder-coated aluminum, polycarbonate |
| Anchoring | 9.8″ raised foundation, no stakes or bolts listed |
| Cold and Snow Note | Not built for heavy snow |
| Customer Rating | 4.6 stars, 60 ratings |
The Outsunny 8.2′ x 6.2′ Greenhouse with Temperature-Controlled Window opens its roof window on its own as the air warms, so a sunny winter afternoon won’t overheat your plants. Built-in raised beds sit on a 9.8″ foundation, keeping roots above the cold ground. It has the most customer ratings of the five.
Pros:
- Automatic venting: No need to be home to open a window.
- Extra side window: A five-level hand-push window adds more airflow.
- Tall hinged door: At 74.4″ high, it is easy to walk through upright.
Cons:
- No anchors listed: Plan to secure the foundation yourself before freeze-up.
- Limited bed space: About 28.8 sq ft of growing area in the beds.
Best For: Busy gardeners who want hands-off ventilation and raised beds in one kit.
4. Best for Family Vegetable Gardens: Outsunny 16′ × 8′ Greenhouse [4]
| Specification | Details |
| Price | $859.99 |
| Overall Size | 8′ W x 16.4′ D x 7.1′ H |
| Frame and Cover | Powder-coated aluminum, 4 mm polycarbonate |
| Anchoring | 4 ground stakes |
| Cold and Snow Note | Not built for heavy snow |
| Customer Rating | 4.6 stars, 16 ratings |
The Outsunny 16′ x 8′ Walk-in Greenhouse gives families over 131 sq ft of rigid growing space. At about $6.55 per square foot, it is the best value of the five. Its 4.5′ eaves suit benches along both sides.
Pros:
- No fixed shelves: Room for raised beds in any layout.
- Rain gutters: Water drains away instead of freezing around the base.
- Corner-friendly: Placing it against a wall or corner improves wind resistance.
Cons:
- Snow needs clearing: Remove snow promptly to protect the roof.
- Narrow 19.3″ door: A full-size wheelbarrow will not fit.
Best For: Families who want to start crops early in spring and harvest late into fall.
5. Best for Small Yards: Outsunny 6′ × 4′ Lean-to Greenhouse [5]
| Specification | Details |
| Price | $294.99 |
| Overall Size | 75.6″ L x 50″ W x 84.3″ H |
| Frame and Cover | Aluminum alloy, 4 mm polycarbonate |
| Anchoring | 4 ground stakes |
| Cold and Snow Note | Windproof Level 4, not built for heavy snow |
| Customer Rating | 4.7 stars, 39 ratings |
The Outsunny 6′ x 4′ Lean-to Greenhouse sits against a wall, which blocks north winds and borrows a little warmth from the house. It has the lowest price and the highest rating of the five. The 84.3″ peak lets you stand upright inside.
Pros:
- Wall shelter: A south-facing wall stores daytime heat.
- Snap-in panels: Quicker to assemble before the ground freezes.
- Water collection: The gutter can feed a rain barrel.
Cons:
- Small growing area: About 26 sq ft of floor.
- Wall-dependent: Stability relies on a sheltered wall.
Best For: Small yards and seed starting against a sunny wall.
How Much Snow Can a Backyard Greenhouse Handle?
A backyard greenhouse handles a few inches of snow well, but heavy buildup should be cleared after every storm. Snow weight varies a lot with moisture. According to FEMA, one foot of fresh snow weighs about 3 pounds per square foot when light and dry, and up to 21 pounds when wet and heavy.[6] By our calculation, the Outsunny 6.2′ x 8.3′ roof load of 8 lbs/ft² equals roughly 4 to 5 inches of wet, heavy snow, or well over 2 feet of light, dry snow.
- Clear after every snowfall: Use a soft broom or roof rake.
- Watch wet storms: Sticky snow near 0°C adds weight fastest.
Polycarbonate vs PE Film: Which Greenhouse Cover Is Better for Canadian Winters?
Polycarbonate is the better cover for Canadian winters. Rigid panels hold heat longer, stand up to wind and stay in place all year, while PE film greenhouses work best for spring and fall season extension.
| Feature | Polycarbonate (All 5 Picks) | PE Film |
| Heat retention | Holds warmth longer after sunset | Loses heat quickly at night |
| Wind resistance | Rigid panels stay firmly in place | Film can flap and tear in strong gusts |
| Snow handling | Rigid roof, cleared after each storm | Film sags under snow weight |
| Winter storage | Stays up all year | Fold or remove before deep winter |
| Price | Higher upfront cost | Usually lower upfront cost |
| Best season | Late fall to early spring | Spring and fall |
Quick tip: If you want to keep growing past October in most of Canada, choose polycarbonate. If you only need an early start in spring, PE film is the budget-friendly option.
Which Greenhouse Suits Your Canadian Hardiness Zone?
Canada’s hardiness zones run from 0 in Nunavut to 9 on Vancouver Island, based on temperature, precipitation and frost. Natural Resources Canada recently updated the map for the first time in over a decade, so check your municipality’s zone before you buy.[7]
| Zone | Best Greenhouse Type |
| 0 to 3 | Picks 1 to 4, used mainly for spring and fall growing |
| 4 to 6 | Any of the five for cold-hardy winter greens |
| 7 to 9 | Any of the five for close to year-round growing |
Which Greenhouse Should You Buy for a Canadian Winter?
The Outsunny 6.2′ x 8.3′ Polycarbonate Greenhouse is the best all-round pick, with the strongest stated snow and wind specs at $429.99. Choose the WWC 8′ x 6′ for a stated -20°C rating, the 16′ x 8′ for family-size growing, or the 6′ x 4′ Lean-to for small yards. Whichever you pick, anchor it before freeze-up and clear the roof after every snowfall.
Find the right greenhouse for your backyard with Aosom Canada, with free shipping on most orders and 30 days to return.
FAQs
Yes, a rigid polycarbonate greenhouse can run year-round in southern Ontario with a heater and regular snow clearing. Without heat, expect it to extend the season from early spring to late fall rather than grow through January.
Aosom Canada is an Ontario-based retailer that sells Outsunny greenhouses online, with free shipping to most of Canada, a 30-day return window and a one-year warranty on its own products. Check ratings before you buy.
Face the long side south to catch the winter sun, which sits low in the sky from November to February. Keep it clear of tall trees and buildings that cast shade, and use a wall or fence on the north side to block cold winds.
The cheapest option is to heat only the plants, not the whole space. Heat mats under seed trays, a small thermostat-controlled electric heater and a well-sealed, south-facing greenhouse keep running costs low through winter.
Yes, even in winter. Sunny days can heat a closed greenhouse fast and trap moisture, which leads to mould and frozen condensation. Open the roof vent for an hour or two around midday, then close it well before sunset.
References
[1] Outsunny 6.2′ x 8.3′ x 6.6′ Greenhouse Kit with Rooftop Vent, PC Board and Sliding Door, Grey, product page.
https://www.aosom.ca/item/outsunny-greenhouse-garden-green-house-outdoor-greenhouse-kit-pc-board-with-slide-door-6-2-x-8-3-x-6-6-grey~1IJQ9NAT5D001.html
[2] WWC 8′ x 6′ Walk-in Polycarbonate Greenhouse with Double Sliding Doors, Black, product page.
https://www.aosom.ca/item/walk-in-polycarbonate-greenhouse-with-double-sliding-doors-galvanized-base-heavy-duty-hothouse-for-plant-94-5-l-x-74-w-x~21LVORQMS5801.html
[3] Outsunny 8.2′ x 6.2′ Greenhouse Aluminum Frame with Temperature Controlled Window, product page.
https://www.aosom.ca/item/outsunny-walk-in-greenhouse-ourdoor-temperature-controlled-window-with-foundation~845-421V02.html
[4] Outsunny 16′ x 8′ Aluminum Polycarbonate Greenhouse, Green, product page.
https://www.aosom.ca/item/outsunny-16-x-8-aluminum-polycarbonate-greenhouse-walk-in-garden-greenhouse-kit-with-adjustable-roof-vent-rain~1R09CJG6K8O00.html
[5] Outsunny 6′ x 4′ Aluminum Lean-to Greenhouse, Clear, product page.
https://www.aosom.ca/item/outsunny-6-x-4-aluminum-lean-to-greenhouse-polycarbonate-walk-in-garden-greenhouse-with-adjustable-roof-vent-rain~1DLF4IQAJ2G00.html
[6] FOX Weather, citing FEMA. Can Your Roof Handle Record-Setting Snow?
https://www.foxweather.com/learn/can-your-roof-handle-record-setting-snow
[7] Natural Resources Canada. Canada’s Plant Hardiness Zone Maps Get an Update.
https://natural-resources.canada.ca/stories/simply-science/zone-canada-s-plant-hardiness-zone-maps-website-get-update