Palram Canopia Mythos 6x8 review
Palram Canopia Mythos 6x8 Greenhouse (Grey)
By Tom Calder
A sturdy, sensibly priced walk-in greenhouse whose twin-wall polycarbonate is far more forgiving than glass around children, pets and stray footballs. A solid, low-drama choice for growing more of your own food, provided you anchor it properly to a firm base.
- Best for
- Households wanting a durable, unheated space to grow their own food and start seedlings year-round.
- Skip it if
- Your plot is very exposed or you can't fix it to a solid, level base
as of 4 Nov 2026, 19:07 GMT · Details
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon.co.uk at the time of purchase will apply to the purchase of this product.We earn a commission if you buy through the retailer links on this page. It doesn't change our verdict. How we make money →
Researched, not used. We haven't used this product. This review is built from the maker's specifications, owner reports and our own sizing.
What we like
- Twin-wall polycarbonate is near-unbreakable and diffuses light well, reducing scorch while blocking UV
- Rust-resistant aluminium frame with a galvanised steel base and integrated guttering
- Good value against a like-for-like aluminium-and-glass greenhouse, and safer to live with
Worth knowing
- Assembly is slow and fiddly, with picture-only instructions and a fair few small parts
- Panels can work loose or pop out in strong winds unless well sealed and anchored
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Our review
Canopia's mid-size hobby greenhouse: a six by eight foot aluminium frame glazed in twin-wall polycarbonate instead of glass. The glazing is the point. Canopia calls it virtually unbreakable, and because the twin skin diffuses light, seedlings get an even glow rather than a scorch. It suits a household that wants a permanent, unheated space to raise plants and stretch the growing season, on a sheltered plot with something solid to bolt it to.
What you get for the footprint
Canopia's UK page lists the 6x8 (model 705561) at 247cm long, 185cm wide and 208cm to the ridge, 124cm at the eaves, with a 56.5cm by 163cm door and 4.6 square metres of floor. The frame is rust-resistant aluminium in grey (RAL 7012), green (RAL 6005) or natural mill-finish silver. Canopia's specification sheet gives the twin-wall panels 82% light transmission, the UK listing we track puts them at 4mm, and the page claims up to 100% UV protection and walls that will not fracture, yellow or turn opaque over time.
The listing also describes a galvanised steel base profile with anchoring holes, but Canopia's FAQ says no floor or foundation comes in the box, nor the screws, masonry anchors or pegs to hold it down.
Twin-wall against clear glazing
Twin-wall polycarbonate is two thin skins joined by ribs with air trapped between them. That air gap is why it holds warmth better than a single clear sheet and why light arrives softened. The cost is brightness: 82% transmission against the 90% Canopia gives for the clear single-skin Harmony 6x4. Canopia pitches the diffused light as gentler on sensitive plants and the twin skin as keeping temperatures more level; for the most light in a dull British spring, clear glazing wins.
Siting, anchoring and wind
Canopia says anchoring is essential to stability and a condition of the warranty: a concrete slab, pressure-treated timber, a deck or paving blocks, with at least 5cm between the base and the foundation edge on every side; firm ground or grass is listed as possible, using ground stakes that are not supplied. Its specification sheet says the Mythos is tested to winds of 56mph (90km/h) and a snow load of 75kg per square metre, and each wall section can carry up to 44lb, about 20kg, of hanging weight. Gusts stronger than that are not unusual in British storms, so an exposed garden is the wrong place for it. A vent opener, shade kit and anchoring kit are sold separately.
How it compares
The Harmony 6x4 is the same height and width but 126cm long, 2.3 square metres of floor, in 0.7mm clear single-skin polycarbonate with the same 56mph rating: half the growing space, but brighter inside. The AMOS walk-in growhouse on the comparison is the soft-cover alternative, 195 by 143 by 143cm, a removable PE cover over 16mm powder-coated steel tubes with eight wire shelves rated to 8kg each; it folds flat but is a seasonal cover rather than a permanent house.
Living with it
Canopia publishes PDF assembly guides for the 6x8, including a one-box version, and an EN 1090 certificate for the frame. It gives no assembly time and links to an assembly service. The door fits one end only, two units cannot be joined, and it can be taken down and moved. The specification sheet gives a five-year warranty, and Canopia's UK support page handles parts requests and assembly help.
Canopia calls it maintenance-free. Its FAQ notes that a greenhouse runs far hotter than outside on a sunny day and falls to the outdoor temperature at night without heating, so plan on the roof vent and shade in summer and fleece for tender plants on a hard frosty night. Our guide to growing your own food covers what an unheated greenhouse realistically adds.
Our verdict
Buy it if you want a real greenhouse rather than a cover, have a sheltered spot and a hard base you are willing to drill, and would rather give up a little light for panels Canopia rates as impact and hail resistant. Skip it if the site is open to the wind, if you cannot anchor it, or if you want the brightest possible house for early sowing, where clear glazing or glass serves better. For a trial season, a soft-cover growhouse from the comparison costs far less.
A researched review, built from the maker's specs, manual and UK listings; facts checked 21 Oct 2026. Sources: Canopia UK: Mythos 6x8 polycarbonate greenhouse (specifications, specification sheet, FAQ, assembly guides); Canopia: Mythos specification sheet (warranty, wind and snow load, light transmission); Canopia: Mythos 6x8 assembly instructions (PDF); Canopia UK: support, parts request and assembly assistance.
Who shouldn't buy this
Your plot is very exposed or you can't fix it to a solid, level base — owners repeatedly report panels dislodging in gales, so a sheltered, firmly anchored spot is essential.
Key specs
| Type | Walk-in hobby greenhouse (aluminium frame, polycarbonate) |
| Size | 6 x 8 ft (approx. 1.85 x 2.5 m) |
| Glazing | 4mm twin-wall diffused polycarbonate (82% light transmission) |
This is a Researched review: we haven't used this product. We check every specification against at least two independent sources, re-check the UK price on a schedule where we can track it automatically, and say plainly who it isn't for. Commissions never change a rating.
If this isn’t the one
Best for First-time growers wanting a low-maintenance, shatter-safe greenhouse for a small garden or patio.
as of 4 Nov 2026, 19:07 GMT · Details
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon.co.uk at the time of purchase will apply to the purchase of this product.
Best for Hardening off seedlings and giving young plants frost protection on a patio or balcony, on a tight budget.
as of 4 Nov 2026, 19:07 GMT · Details
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon.co.uk at the time of purchase will apply to the purchase of this product.
Best for Cheaply extending the growing season or hardening off seedlings on a patio or allotment.
as of 4 Nov 2026, 19:07 GMT · Details
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon.co.uk at the time of purchase will apply to the purchase of this product.Questions
Does the Palram Canopia Mythos 6x8 come with a base?
The frame sits on a galvanised steel base profile with anchoring holes, but Canopia's FAQ says no floor or foundation is included and that screws, masonry anchors and ground stakes are not supplied. You need a level slab, timber frame, deck or paving to fix it to, and anchoring is a condition of the warranty.
Is the Mythos 6x8 twin-wall or single-skin polycarbonate?
Twin-wall only. Canopia offers the Mythos solely in twin-wall glazing, with 82% light transmission on its specification sheet; the UK listing gives 4mm panels. The Harmony range is the clear single-skin alternative.
How much wind can the Mythos 6x8 take?
Canopia's specification sheet says it is tested to 56mph (90km/h) winds and a 75kg per square metre snow load. That assumes it is properly anchored to a firm base, which Canopia makes a condition of the warranty.
How big is the Mythos 6x8 inside?
Canopia lists 247cm by 185cm externally, 208cm to the ridge, 124cm at the eaves and 4.6 square metres of floor. The door is 56.5cm wide and 163cm tall, so anyone taller than that ducks on the way in.
Can I take the Mythos 6x8 down and move it?
Yes. Canopia's FAQ says its greenhouses can be disassembled, relocated and reassembled, which matters in a rented garden. Two units cannot be joined together, and the door fits one end only.
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