Palram (Canopia) Greenhouses: The Honest Review for Ontario Growers

Reading Time: 13 minutes

Where We Stand

This review is written by a shipping container yard in Brantford, Ontario. We are not affiliated with Palram or Canopia, we receive nothing from them or from Costco, Canadian Tire or Home Depot, and we do not sell greenhouse kits. What we sell is the steel box that becomes a container greenhouse or a year-round grow room, which competes with a polycarbonate kit only for the grower who wants to keep going past November, and that is the last third of this page and the only place we have a stake. Everything about the company and its greenhouses below comes from canopia.com, palram.com and the Costco.ca and retailer listings, read on September 15, 2026. Where we describe a limit, it is one the company’s own specifications or warranty make plain; we make no claims about how the company conducts itself. The greenhouse kits guide for Canada is the category page; this one is Palram alone.

Who Palram Is, and What Canopia Means

Palram Industries was established in 1963 at Kibbutz Ramat Yohanan in northern Israel as a maker of plastic sheet, and it is now a multinational manufacturer of polycarbonate and PVC panels with plants and branches on six continents, publicly traded in Tel Aviv, whose sheet goes into everything from stadium roofs to the twin-wall you see on a backyard greenhouse. Canopia by Palram is the consumer brand the company adopted a few years ago for its do-it-yourself greenhouses, carports, pergolas, gazebos and sheds, so the box at Costco says Canopia and the older listings say Palram, and they are the same product. That matters for one reason: Palram makes the polycarbonate itself, which is why the panels are the best thing about the kit and why the warranty is written around them. In Canada the greenhouses reach the buyer through Costco, which carries the Glory Premium 8×8 and the Build and Grow Hybrid line, and through Canadian Tire, Home Depot, Amazon and greenhouse dealers. The Costco backyard-building shelf is our page on where the Palram sits beside the sheds.

The Lineup, Decoded

All of them are the same object: an aluminum frame, a galvanized steel base on most models, polycarbonate panels that slide or clip into the frame, a roof vent or two, a lockable door, and a flat box of parts. The panel is the choice, and the section below is about it. Our container greenhouse build is where the same choice gets made in steel and glass.

Twin-Wall, Clear and 10 mm: What the Panel Decides

Polycarbonate comes to a greenhouse in three forms and Palram sells all three. Clear single-sheet polycarbonate lets in the most light and holds the least heat, which is right for a spring seed house and wrong for anything meant to stay warm at night. Twin-wall, two thin skins with air channels between them, usually 4 or 6 millimetres thick, diffuses the light, which plants like, and holds a few degrees more overnight, at the cost of some brightness and a channel that collects algae and condensation if the ends are not sealed. Ten-millimetre twin-wall, on the Glory, is the same idea with a thicker air gap and the stiffness to carry more snow, which is why it carries the longer warranty. All of Palram’s panels are UV-protected, which is the property that separates a polycarbonate that lasts a decade from a vinyl or a polyethylene film that clouds and cracks in three summers, and it is what a buyer is paying for in a polycarbonate kit. The supplemental lighting page is where the light that a panel lets in stops being enough and lamps take over.

Strengths First

The strengths are real. The polycarbonate is made by the company that sells the kit, it is UV-stabilized on the outer face, and it does what the brochure says for the years the brochure promises, which is more than most kit greenhouses can claim. The aluminum frame does not rust, the galvanized base on the larger models gives the frame something square to stand on, and the roof vents and lockable door are included rather than sold as accessories. The range is the widest in the box stores, from a 6×4 lean-to to an 8×20, in three panel types, so a buyer can match the panel to the season they mean to grow in. The Glory’s 10-millimetre panels and 10-year warranty are a genuine step up from anything else on the shelf. Costco’s distribution puts the Hybrid and the Glory where a buyer can see one and return one, and the automated vent opener and shelving accessories exist as a catalogue. And the instructions, for a kit with several hundred parts, are better than average. The fish-and-greens aquaponics guide is one of the things a grower ends up putting inside one.

The Snow and Wind Ratings, Read Against Ontario

Palram publishes ratings, which most greenhouse makers do not, and they have to be read against the province. The Mythos, Hybrid and Harmony are rated for a snow load of 75 kilograms per square metre, which is about 15 pounds per square foot or three-quarters of a kilopascal, and wind of 90 kilometres an hour. Ontario’s design snow load is about a kilopascal along the Lake Erie shore and two to three times that in the snowbelt east of Georgian Bay, the Ottawa Valley and the north, so the standard Palram is rated for less than a Windsor winter and much less than a Barrie one, which is why the manual says to clear the roof and why most owners take the panels out or drop a tarp over the frame from December to March. The Glory’s thicker panel carries more, per its own spec sheet, and it is still a greenhouse roof rather than a building roof. The wind figure, 90 kilometres an hour, is a real gale and it assumes the kit is anchored to its base and the base to the ground; the Reddit question about whether a Palram survives wind is answered by the anchors, not the frame. The container roof’s stacking rating is the figure for the one growing building that never needs the shovel.

The Documented Trade-Offs

Four, all in the specifications. The snow rating above, which makes every model but the Glory a three-season structure in most of Ontario without clearing or covering. The assembly, several hundred parts, panels that slide into channels that must be square, and a manual that assumes a level base and a calm day; a 6×8 Hybrid is a long day for two people and an 8×12 Glory is a weekend, and the panels crack if forced. The heat: a polycarbonate greenhouse with no heat source is a cold frame with a door in January, and a 6×8 with a small electric heater is a real expense that the kit price does not hint at. And the base: the kit includes a base frame on most models but not what the base sits on, and a Palram on lawn heaves with the frost and pops its panels by the second spring. None of that is hidden; it is on the box and in the manual. The container greenhouse cost and build page works through what heating a growing space through an Ontario winter actually involves.

The Base, the Anchors and the First Gale

A polycarbonate greenhouse is a light box with a lot of sail area, and its two failures are the same as a fabric shelter’s: it lifts in wind and it heaves on frost. The fix is the base and the anchors. Build a level, drained pad of compacted crushed stone a foot bigger than the kit, or a perimeter of patio stones or a treated-timber frame on gravel, and bolt the galvanized base to it; on soil, drive the auger anchors the manual calls for through the base, because the frame’s own weight is nothing against a west wind. Then seal the twin-wall panel ends with the tape the better dealers sell, so the channels stay clear, and fit the automated vent opener, because a closed polycarbonate box in June cooks a tomato by noon. The crushed-stone pad how-to is the base under either building, and the container anchoring question is the contrast: a box on gravel mostly is not, because it weighs 5,000 pounds.

What a Palram Does in an Ontario Winter

Three things, depending on the model and the owner. Left up and unheated, a Palram is a cold frame: it keeps the frost off hardy greens a few weeks longer in the fall and lets them start a few weeks earlier in the spring, and it holds nothing above freezing in January. Left up and heated, a Mythos or a Glory with the ends sealed and a small heater on a thermostat keeps a shoulder-season crop going and overwinters tender plants, at a hydro cost the owner should price before December; the twin-wall and the 10-millimetre panels are the difference between a heater that runs half the night and one that runs all of it. And cleared or covered, which is what the manual and the snow rating imply for the standard models: the roof shovelled after every fall, or the panels pulled and stored, or a tarp over the frame, from the first real snow to March. The Glory is the model built to skip the third option in southern Ontario. The nursery overwintering page is where the overwintering problem gets its own building.

Which Model for Which Grower

The Harmony is built for maximum light from March to May, the seed-starting months, and gets stored or covered in winter. The Hybrid, sold at Costco as Build and Grow, is the first-greenhouse size for a suburban yard: tomatoes and peppers from April to October, cleared in winter. The Mythos puts the twin-wall’s heat retention on every face, for a windy or shaded spot. The Balance and Snap and Grow run 8 feet wide, with a real path between benches. The Glory carries the 10-millimetre panel and the 10-year warranty for a grower who heats it into November and out of February in southern Ontario. Growing all year takes a heated, lit, insulated building, which is the next section. The market garden wash and pack page is the other steel box a serious grower ends up with.

Where the Container Fits

A shipping container is the year-round answer to the question a Palram stops answering in November, and each building has its own job. The polycarbonate kit’s job is light: it is a transparent building, and nothing in steel grows a tomato in April on sunlight alone. The container’s job is winter: a 20 or 40-foot box foamed with closed-cell spray, lit with LED grow lights, ventilated and heated with a mini-split, is a sealed, insulated, lockable grow room that holds 20 degrees in February on a fraction of the hydro a heated polycarbonate box burns, and it is the building behind every hydroponic, microgreen and mushroom operation that grows in a Canadian winter. The two are more often paired than chosen: the Palram for the sun months and the seedlings, the container for the winter greens, the propagation and the cold storage. The hydroponic container grow page is the year-round room in detail, the container greenhouse page is the hybrid, a container with a polycarbonate or glass roof grafted on, and the foam-first insulation guide is why the foam is the first thing that goes in.

What goes into the room. A container grow room is a windowless, lit, engineered room rather than a greenhouse, and the lights, the ventilation, the dehumidification and the electrical service are trades of their own, quoted on top of the box. A container with a polycarbonate roof cut into it is a real build with a real engineer. The room starts from a one-trip 20-foot dry container, square and clean, from the one-trip rows on Morton Avenue East at 90 Morton Avenue East, because every cut assumes a square, clean box, foamed and fitted with the door and the vents at the modification shop that cuts the vents before it leaves; the cold storage beside the Palram is a used 20-foot refrigerated container, factory-insulated, from the used rows. Every unit lands on a gravel pad anywhere in the delivery area, growing zone by growing zone in one to three days with payment on delivery. Everything is sold outright; Van Blanc keeps no rental fleet.

Palram or Container Grow Room: What Each Is For

A Canopia Hybrid or Mythos from Costco is a first greenhouse that wants a level gravel pad, anchors, sealed panel ends and the vent opener, and a cleared or covered roof in winter. The Glory is the Palram built to be heated into the shoulder seasons in southern Ontario, with one job before December: price the hydro first. Growing through February is the container grow room’s work: one-trip steel, foamed, lit and heated, set on its pad in one to three days and paid for on delivery, and it sits beside the greenhouse when the plan is to grow all year. The garden-building alternatives hub is the wider read for anyone still deciding what kind of building the garden needs at all.

The two pages that finish this one are the greenhouse kits guide, which compares Palram with the glass, film and cedar kits, and the reefer as cold storage, for the cold storage a market garden adds next.

Reach Van Blanc in Brantford

We have been supplying shipping containers across Ontario since 1995. Our yard is at 90 Morton Avenue East in Brantford, and we deliver right across the province with payment on the day of delivery. No deposit, no upfront wires, no chase-the-paperwork.

Van Blanc Ent. Inc., 90 Morton Ave E Unit 1B, Brantford, ON N3R 7J7, 519-754-6844 (cell) or 1-888-509-6658 (toll-free).

If the greenhouse you were pricing needs a winter half somewhere in this page, call with what you grow and your postal code and we will tell you on the spot what is in the one-trip rows and how the shop would fit it out. Worth the drive for unbeatable quality, family customer service with 30 years of experience.

Related Reading

• Greenhouse Kits in Canada: The Honest Buyer’s Map
• Container Greenhouse Ontario: Year-Round Container Farming
• The Hydroponic Container Grow Room, Ontario Edition
• Container Greenhouse Canada: Cost and Build
• Aquaponics in Ontario: The Guide