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A backyard greenhouse that lasts comes down to three decisions: put it in full sun on a level, anchored base; size it one step bigger than you think; and match the kit to your winter. For most yards, the Palram Mythos 6x8 is the best starter. Cold, snowy regions should look at the Riverstone MONT 8x12 (24 psf snow, 65 mph wind). For high wind, the Janco Palmetto 8x10 carries the strongest published ratings of any rigid kit we found. For the most growing space per dollar, a 10x12 hoop house wins.
- 1Best starterPalram Mythos 6x8
First real greenhouse in a cold-ish climate on a budget; twin-wall all round for heat retention.
Wind56 mphSnow15.4 psf$689–$889typical, Oct 2026 - 2Wind65 mphSnow24 psf$4,150–$7,100typical, Oct 2026
- 3Best for high windJanco Palmetto 8x10 (Glass)
US-made aluminum/glass greenhouse with the highest published wind and snow ratings in this set.
Wind120 mphSnow50 psf$2,500–$6,000typical, Oct 2026 - 4No published wind or snow rating$5,046typical, Oct 2026
- 5No published wind or snow rating$6,500–$8,526typical, Oct 2026
- 6Wind56 mphSnow15.4 psf$1,250–$4,449typical, Oct 2026
- 7Wind56 mphSnow15.4 psf$3,000–$4,199typical, Oct 2026
- 8Most space per dollarBootstrap Farmer 10x12 Hobby Hoop House
Backyard hoop house that fits typical 120 sq ft HOA/accessory-structure limits.
No published wind or snow rating$650typical, Oct 2026
Most of the backyard greenhouse content that ranks today is Pinterest boards and Reddit threads: great for inspiration, thin on the decisions that make a greenhouse last. This guide walks through those decisions in order (what you'll grow, where it goes, size, permits, base, kit) and then lists the kits worth buying. Picks are based on manufacturer specs, retailer listings and owner reports. We haven't assembled them ourselves; here's how we research.
Step 1: Decide what you'll grow, and when
This decides almost everything else, especially the cover material and whether you'll heat it.
| Your plan | Season | Cover to choose | Heat? |
|---|---|---|---|
| Start seeds, harden off transplants | Late winter to spring | Clear or hybrid polycarbonate, or film | Maybe a small heater on frost nights |
| Tomatoes, peppers, cucumbers | Spring to fall | Twin-wall or hybrid polycarbonate | No, but you need ventilation and shade |
| Overwinter citrus and tender plants | Fall to spring | Twin-wall polycarbonate, thicker the better | Yes, to stay above freezing |
| Grow greens all winter | Year-round | 8-10 mm twin-wall or more | Usually, in cold zones |
| Garden room or sunroom | Year-round | Hybrid (twin-wall roof, clear walls) or glass | Optional |
Twin-wall polycarbonate gives about twice the heat retention of single-layer panels according to Palram-Canopia, and published R-values climb with thickness: 1.53 for 6 mm twin-wall, 2.1 for 10 mm four-wall, 3.0 for 16 mm triple-wall. If winter growing is the goal, read our winter greenhouse guide before you buy.
Step 2: Where to put a greenhouse in your backyard
- Maximum winter sun. Watch the spot in winter if you can: the sun is low and long shadows from the house, fences and evergreens fall much further than in summer. Deciduous trees to the south are less of a problem since they drop their leaves.
- Orientation. For year-round use, run the ridge east-west so the long side faces south. For summer-only use, it matters less.
- Wind shelter. A hedge or fence on the prevailing-wind side reduces load on light kits. Don't tuck it so tight that you can't reach the panels.
- Drainage. Avoid low spots. Water pooling under the base undermines it and keeps the floor wet.
- Water and power. Within hose reach at minimum. If you'll run fans or a heater, plan a GFCI-protected outdoor circuit, installed to code.
- Access. A path wide enough for a wheelbarrow, and door clearance on the side you'll use most.
- Against the house? A south wall is a natural heat store. If that's your best spot, consider a lean-to greenhouse.
Step 3: Pick the right size
Width decides how you work inside; length decides how much you grow. A 6-ft-wide greenhouse fits benches on both sides with a 2 ft path. An 8-ft width lets you add raised beds or a potting bench. Bench space fills faster than most people plan for, so if two sizes fit your space and budget, choose the larger.
| Size | Area | Best for |
|---|---|---|
| 6x8 | 48 sq ft | Seed starting plus a summer of tomatoes and peppers |
| 8x8 / 8x10 | 64-80 sq ft | Benches plus a bed; room to work |
| 8x12 / 10x12 | 96-120 sq ft | Serious hobby growing; overwintering plus growing |
| 12x12 and up | 144+ sq ft | Garden room, seating, or near-market-garden output (may need a permit) |
Size guides: small greenhouse kits (up to 8x8), 8x10 greenhouses and larger walk-in greenhouses.
Step 4: Permits, HOAs and neighbors
The International Residential Code, which most US towns adopt in some form, exempts one-story detached accessory structures up to 200 sq ft from a building permit (section R105.2). Many towns set the line lower, at 120 sq ft. Either way, the exemption doesn't override zoning: setbacks from property lines, height limits and lot-coverage rules still apply, and electrical or plumbing work usually needs its own permit. HOAs often require approval for any outdoor structure, so ask before you order. A call to your building department takes ten minutes and can save you moving a greenhouse.
Step 5: Plan the base
Every kit needs a level, anchored base; it's the single biggest factor in how a light greenhouse handles wind. Options run from pavers on compacted gravel (light 6-ft kits) to pressure-treated timber frames (most aluminum and hoop kits) to concrete or block perimeter walls (glass and heavy kits). Some kits need a separate base frame: Exaco's RIGA base frame, for example, is sold separately at Eartheasy. Our greenhouse foundation guide walks through each.
The best backyard greenhouse kits
Palram Mythos 6x8
For a first backyard greenhouse, the Mythos hits the sweet spot: twin-wall polycarbonate all round, an aluminum frame on a galvanized steel base, published 56 mph wind and 15.4 psf snow ratings, and a 5-year warranty. Eartheasy sells the full 6-ft family from 6x4 up to 6x14, so you can size it to your yard.
Why it stands out
- Best insulation at its price
- Six lengths on one frame
- 4.3/5 from 704 Wayfair reviews
Watch out for
- Anchor and brace it: one owner's 6x8 was wrecked by about 30 mph gusts until he added locknuts and angle bracing
- Narrow 1'10" door
Full specs
- Sizes
- 6x8 (also 6x4, 6x6, 6x10, 6x12, 6x14)
- Footprint
- 6.1 x 8.1
- Peak height
- 6.8 ft
- Frame
- Powder-coated (green/grey) or mill-finish silver aluminum frame on galvanized steel base
- Panels
- 4 mm twin-wall polycarbonate, roof and walls (diffused light)
- Vents
- 1 manually adjustable roof vent (auto opener sold separately)
- Door
- Hinged single door, 1'10" x 5'4" opening (Canopia spec), lockable with magnetic catch
- Snow load
- 15.4 lb/sq ft
- Wind rating
- 56 mph
- Warranty
- 5-year limited (Eartheasy listing)
Specs from eartheasy.com, canopia.com. Prices checked Oct 2026 and change often.
Riverstone MONT 8x12
The MONT is built for places where cheaper kits fail. Heavy extruded aluminum, 8 mm twin-wall panels, automatic roof vents and published ratings of 24 psf snow and 65 mph wind, with a 10-year warranty (15 on the Growers package). Eartheasy sells it as a greenhouse only, a Deluxe kit, a hot-climate Mojave package with a tinted roof and solar fan, or a turnkey Growers package with electric ventilation and a 17,000 BTU heater.
Why it stands out
- Among the highest published snow and wind ratings of the kits we checked
- Packages for hot climates and heated winter growing
- Made in the USA; extends in 4-ft sections
Watch out for
- Low 4'10" sidewalls
- Installation can take several days (dealer note)
- Packages add cost fast
Full specs
- Sizes
- 8x12 (also 8x16, 8x20, 8x24; Mojave and Growers packages)
- Footprint
- 8.4 x 12.5
- Peak height
- 7.5 ft
- Frame
- Extruded aluminum, integrated base
- Panels
- 8 mm twin-wall polycarbonate (Mojave: tinted roof; Growers: light-diffusing)
- Vents
- Automatic roof vents; Mojave adds solar fan, Growers adds electric ventilation + 17,000 BTU heater
- Door
- Hinged lockable double doors, 6 ft x 4 ft opening
- Snow load
- 24.0 lb/sq ft
- Wind rating
- 65 mph
- Warranty
- 10-year (Growers 15-year)
Specs from eartheasy.com, eartheasy.com. Prices checked Oct 2026 and change often.
Janco Palmetto 8x10 (Glass)
Janco builds the Palmetto by hand in the USA and states it is designed to exceed 120 mph wind and 50 psf snow, the highest published ratings in our data. Choose tempered glass or 8 mm twin-wall polycarbonate, and a mill, bronze or white aluminum frame. A passive solar ridge vent opens between about 55°F and 75°F, and the glass and frame carry a lifetime warranty.
Why it stands out
- Highest published wind and snow ratings we found
- Lifetime warranty on glass and frame
- Glass or polycarbonate option
Watch out for
- Needs anchoring to a wood or concrete foundation
- No owner reviews we could verify
Full specs
- Sizes
- 8x10
- Footprint
- 8.0 x 10.0
- Frame
- Aluminum (mill, bronze or white), handmade in USA
- Panels
- 1/8" tempered safety glass or 8 mm twin-wall polycarbonate (option)
- Vents
- Passive solar ridge vent (opens 55-75 F)
- Door
- Heavy-duty aluminum full-lite door
- Snow load
- 50.0 lb/sq ft
- Wind rating
- 120 mph
- Warranty
- Lifetime on glass and metal frame
Specs from eartheasy.com. Prices checked Oct 2026 and change often.
Outdoor Living Today Cedar 8x12
If the greenhouse will be a feature of the yard, a cedar frame looks the part and insulates better than metal. This Western red cedar 8x12 comes pre-cut and panelized with 6 mm twin-wall panels (R-1.53), two heat-activated roof vent openers plus two lower wall vents, and 24 lineal feet of shelving.
Why it stands out
- Shelving and automatic vents included
- Room for a full shelving run plus a potting bench
- Free freight from Eartheasy
Watch out for
- Only a 1-year manufacturer warranty
- Floor and foundation are extra
Full specs
- Sizes
- 8x12
- Footprint
- 8.0 x 11.8
- Peak height
- 8.7 ft
- Frame
- Western red cedar, pre-cut panelized
- Panels
- 6 mm Polygal twin-wall polycarbonate (R-value 1.53)
- Vents
- 2 heat-activated roof vent openers (~70 F) + 2 lower wall vents
- Door
- Full polycarbonate door
- Warranty
- 1-year manufacturer
Specs from eartheasy.com. Prices checked Oct 2026 and change often.
Exaco RIGA IIIS
The RIGA's steep arched roof is designed to shed snow, and its panels are thick: 8 mm twin-wall on the sides and 10 mm on the gable ends. A 40 x 24 inch roof window and a back wall window handle ventilation, the Dutch barn door lets you vent just the top half, and Exaco gives a 10-year limited warranty. Exaco doesn't publish a psf rating in the listings we read, so judge it on design and warranty.
Why it stands out
- Arched roof sheds snow
- Thick 8-10 mm twin-wall panels
- Oversized roof window and Dutch door for ventilation
Watch out for
- Base frame sold separately
- Can't be lengthened after assembly
Full specs
- Sizes
- 7.7x10.5 (RIGA IIS 7.7x7, III 9.7x10.5, IVs 7.7x14, IV/V 9.7x14)
- Footprint
- 7.7 x 10.5
- Peak height
- 7.1 ft
- Frame
- Smooth anodized aluminum, profiles permanently attached
- Panels
- 8 mm twin-wall sides, 10 mm twin-wall front/back, semi-diffused
- Vents
- 1 oversized roof window (40" x 24") with opener + back wall window
- Door
- Lockable dutch barn door, 30" wide
- Warranty
- 10-year limited (Exaco)
Specs from eartheasy.com, exaco.com. Prices checked Oct 2026 and change often.
Palram Oasis Hexagonal
Not every backyard greenhouse is about yield. The Oasis is a six-sided greenhouse with a twin-wall roof and clear walls (82% overall light transmission per Palram) and lockable double doors, designed to be looked at as much as grown in. Eartheasy sells 8-ft and 12-ft-wide versions; Costco also lists it, so check which size a price refers to.
Why it stands out
- Distinctive shape that works as a garden centerpiece
- 56 mph wind and 15.4 psf snow ratings
- Steel base included
Watch out for
- Less bench space per dollar than a rectangle
- Side louver windows only, no roof vent listed
Full specs
- Sizes
- 8 ft wide (also 12 ft wide)
- Footprint
- 7.0 x 8.0
- Peak height
- 8.8 ft
- Frame
- Grey aluminum frame, galvanized steel base
- Panels
- 4 mm twin-wall roof + 0.7 mm clear polycarbonate walls (82% overall light transmission)
- Vents
- Side louver window(s)
- Door
- Lockable double doors
- Snow load
- 15.4 lb/sq ft
- Wind rating
- 56 mph
Specs from eartheasy.com, canopia.com. Prices checked Oct 2026 and change often.
Palram Americana 12x12
At 144 sq ft, the Americana is a barn-style greenhouse with room for benches, beds and a couple of chairs. It pairs a twin-wall roof with clear walls, has two roof vents and high double doors with a low threshold, and includes an anchoring kit, which the 56 mph wind rating assumes you use. At 144 sq ft it is over the common 120 sq ft permit line, so check locally.
Why it stands out
- Space to grow and sit
- Anchoring kit included
- Sold at Eartheasy; Costco bundles an accessory pack
Watch out for
- May need a permit in towns with a 120 sq ft limit
- Mixed owner ratings (Walmart 3.9/5 on 37)
Full specs
- Sizes
- 12x12
- Footprint
- 12.0 x 12.0
- Peak height
- 8.6 ft
- Frame
- Reinforced silver aluminum frame, galvanized steel base, anchoring kit included
- Panels
- 4 mm twin-wall roof + crystal-clear SnapGlas polycarbonate walls
- Vents
- 2 roof vents
- Door
- High lockable double swing doors, low threshold
- Snow load
- 15.4 lb/sq ft
- Wind rating
- 56 mph
Specs from eartheasy.com, canopia.com. Prices checked Oct 2026 and change often.
Bootstrap Farmer 10x12 Hobby Hoop House
If the goal is food, a hoop house gives you the most in-ground growing space for the money: 120 sq ft under 6 mil film rated for 4 years, on 1 3/8-inch galvanized steel hoops with 36-inch ground stakes. You add baseboards and hipboards from a local lumber yard, plus a door kit.
Why it stands out
- 120 sq ft for about the price of a name-brand 6x8
- Grow directly in the ground
- Ships in boxes, no freight
Watch out for
- Film needs replacing every few years
- Extra anchoring or snow clearing needed in snowy, windy areas
Full specs
- Sizes
- 10 x 12 (120 sq ft)
- Footprint
- 10 x 12
- Peak height
- 7.9 ft
- Frame
- 1 3/8 in galvanized steel, 3 pre-bent hoops plus ridge pole
- Cover
- 6 mil greenhouse plastic, 4-year rating
- Door
- Not included (scissor door or end-wall door frame kit sold separately)
- Warranty
- Plastic: 4-year rating
Specs from bootstrapfarmer.com. Prices checked Oct 2026 and change often.
Backyard greenhouse kits compared
| Model | Sizes | Panels | Snow load | Warranty | Typical price | Shop |
|---|---|---|---|---|---|---|
| Palram - Canopia Mythos 6' x 8' Greenhouse Kit | 6x8 (also 6x4, 6x6, 6x10, 6x12, 6x14) | 4 mm twin-wall polycarbonate, roof and walls (diffused light) | 15.4 lb/sq ft | 5-year limited (Eartheasy listing) | $689–$889 | Eartheasy |
| Riverstone MONT Greenhouse 8' x 12' | 8x12 (also 8x16, 8x20, 8x24; Mojave and Growers packages) | 8 mm twin-wall polycarbonate (Mojave: tinted roof; Growers: light-diffusing) | 24.0 lb/sq ft | 10-year (Growers 15-year) | $4,150–$7,100 | Eartheasy |
| Janco 8' x 10' Palmetto Greenhouse | 8x10 | 1/8" tempered safety glass or 8 mm twin-wall polycarbonate (option) | 50.0 lb/sq ft | Lifetime on glass and metal frame | $2,500–$6,000 | Eartheasy |
| 8' x 12' Western Red Cedar Greenhouse | 8x12 | 6 mm Polygal twin-wall polycarbonate (R-value 1.53) | — | 1-year manufacturer | $5,046 | Eartheasy |
| Exaco RIGA IIIS Greenhouse (7'8" x 10'6") | 7.7x10.5 (RIGA IIS 7.7x7, III 9.7x10.5, IVs 7.7x14, IV/V 9.7x14) | 8 mm twin-wall sides, 10 mm twin-wall front/back, semi-diffused | — | 10-year limited (Exaco) | $6,500–$8,526 | Eartheasy |
| Palram - Canopia Oasis Hexagonal Greenhouse | 8 ft wide (also 12 ft wide) | 4 mm twin-wall roof + 0.7 mm clear polycarbonate walls (82% overall light transmission) | 15.4 lb/sq ft | — | $1,250–$4,449 | Eartheasy |
| Palram - Canopia Americana 12' x 12' Greenhouse | 12x12 | 4 mm twin-wall roof + crystal-clear SnapGlas polycarbonate walls | 15.4 lb/sq ft | — | $3,000–$4,199 | Eartheasy |
| Hobby Greenhouse Kit 10' x 12' | 10 x 12 (120 sq ft) | — | — | Plastic: 4-year rating | $650 | Bootstrap Farmer |
What a backyard greenhouse really costs
The kit is only part of the bill. Budget for these as well:
| Item | Why you need it | Notes |
|---|---|---|
| Base or foundation | Level, anchored surface | Pavers or timber for light kits; perimeter foundation for glass. Exaco's RIGA base frame alone is sold separately. |
| Anchors and bracing | Wind resistance; warranty condition on some brands | Ground anchors, locknuts, aluminum angle |
| Automatic vent opener | Prevents overheating | Included on Riverstone, Glory, cedar and Janco kits; extra on most Palram 6-ft kits |
| Shelving and benches | Growing space | See greenhouse shelving |
| Heater and thermostat | Winter growing | See greenhouse heaters |
| Water and power | Daily care, fans, heat | Outdoor electrical work usually needs a permit |
Full ranges by size and material are in our greenhouse cost guide.
Backyard greenhouse mistakes to avoid
- Siting it in summer. A spot that's sunny in June can be in the house's shadow all of December.
- Skipping the anchors. Light kits blow over or lose panels in the first big gust.
- Underestimating heat. Overheating kills more seedlings than cold. Fit auto vents and plan shade cloth; see greenhouse ventilation.
- Buying clear walls for winter growing. They're bright but lose heat fast.
- Not checking permits and the HOA. Especially for anything over 120 sq ft.
- Going too small. Only some kits extend later (the Riverstone MONT in 4-ft sections and Palram's Snap & Grow line do; the Exaco RIGA can't).
Alternatives and next steps
Not ready for a permanent structure? A portable greenhouse or cold frame extends the season for much less. Want storage too? See greenhouse shed combos. If you're leaning toward wood, our wooden greenhouse kits page compares cedar options, and glass greenhouse kits covers glass versus polycarbonate.
Frequently asked questions
Where is the best place to put a greenhouse in a backyard?
The sunniest open spot you have, with the long side facing south, on level ground that drains well. Keep it clear of evergreen shade, out of the strongest prevailing wind, and close enough to a hose (and ideally an outdoor outlet) that daily care is easy.
Do I need a permit for a backyard greenhouse?
Often not for a small one. The model residential code (IRC R105.2) exempts one-story detached accessory structures up to 200 sq ft, and many towns use 120 sq ft. Setbacks, height limits, HOA rules and any electrical work still apply, so check with your building department before ordering.
What size greenhouse is best for a backyard?
6x8 ft is the most common starter size; 8x12 is the size most serious hobby growers end up wanting. If you can fit and afford one size bigger than you think you need, buy it.
How long do backyard greenhouse kits last?
Aluminum and polycarbonate kits from established brands carry 5- to 10-year warranties (Palram 5, Riverstone and Exaco 10, Janco lifetime) and typically outlast them. Film-covered hoop houses need new film every few years; 6 mil kit film is rated for about 4 years.
Should a backyard greenhouse face north-south or east-west?
For year-round growing in most of the US, run the ridge east-west so the long side faces south and catches low winter sun. For spring-to-fall growing only, orientation matters less; a north-south ridge gives more even light through the day.
Does a backyard greenhouse need a foundation?
Yes. Almost every kit needs a level, anchored base, and anchoring is a warranty condition for brands like Palram-Canopia. Pavers on gravel or a pressure-treated timber frame work for light kits; glass and heavy kits need a proper perimeter foundation.
Keep reading
Kits by sizeSmall greenhouse kitsCompact greenhouse kits from 6x4 to 8x8: which one fits your yard, budget and winter.
Build guideGreenhouse foundations and basesEvery greenhouse base option compared, with step-by-step timber and paver builds, squaring, anchoring and flooring.
Cost guideHow much a greenhouse costsGreenhouse prices by type and size, cost per square foot, the hidden extras and what heating really costs per night.
Kits by typeWalk-in greenhouse kitsWalk-in greenhouses from cheap film shelters to large heavy-duty kits, compared on headroom, doors and storm ratings.
Growing guideWinter greenhouse guideKeep a greenhouse productive in winter: what to grow, how big a heater you need, insulation, thermal mass and safety.
Kits by typePolycarbonate greenhouse kitsTwin-wall vs clear panels, thickness and R-values, plus six aluminum hobby kits from starter 6x8s to snow-country builds.