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Planta

Planta Sungrow 20 (Gen III)

Its structural ratings are published in the assembly manual — not on any retailer product page.

23 of 45 fields researched · last updated 2026-08-29

What the manual says that the product page doesn't

MANUAL says 'wind speeds no more than 100 km/h (65 mph)'. The PRODUCT PAGE says 60 mph. Manufacturer's own documents disagree with each other; we report the manual figure and flag the conflict rather than silently choosing. This also resolves the 60-vs-65 discrepancy against our earlier competitor research, which had 65.

source document

Automatic roof vents are an upsell, explicitly not in the kit.

source document

MANUAL, verbatim: 'Roof vents are not included in this kit. We highly recommend adding Sungrow automatic roof vents to your order.' The kit ships with two door openings and two ventilating windows at opposite ends only. The product page's ventilation claims do not make this absence obvious.

source document

Structure

Width10 ft source
Length20 ft source
Floor area200 sq ft source
Framehot-dip galvanised steel source
Glazing6mm UV-protected polycarbonate source
Panel thickness6 mm source
Panel retentionnot published

Wind, snow and anchoring

Wind rating65 mph source from the manual
…which assumesRated to 65 mph provided the specified loads are not exceeded; the manual states panels need not be removed in winter provided those loads hold source from the manual
Snow load75 psf source from the manual
Snow depthnot published
Anchoring includedYes source
What ships for anchoringgalvanised steel legs set about 1 ft into the ground, plus included ground anchors / angle brackets source
Foundation requiredsuitable ground with ground anchors, or the buyer's own foundation source

Ventilation

Roof vents0 source from the manual
Side / end vents2 source from the manual
Opening windowsNo source from the manual
Doors2 source

Ownership

ExpandableYes source
Replacement panelsmanufacturer sells polycarbonate sheets in 6/8/10/16/25mm source

Where to buy

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Climate notes

Our analysis of the published figures — not a manufacturer claim.

Hot climates
NO ROOF VENTS in the kit — ventilation is two end windows and two doors only, with automatic roof vents sold separately. For a 200 sq ft footprint that is thin, and community reports describe 110-120F interiors even with powered fans. Budget the roof vent kit and a fan from the outset.
Cold climates
75 psf snow load, stated in the manual, is the strongest in our set — five times the Palram Essence's 15 psf. The manual states panels need not be removed in winter provided the load ceiling is not exceeded. Caveat: the supplied legs go about 1 ft into the ground and do not reach frost depth in most cold regions, so a proper base is worth costing in.
Exposed and windy sites
60 mph is modest against a Bellerose's claimed 100 mph, but Planta INCLUDES the anchoring its rating depends on, whereas most brands state the condition and leave the buyer to source it. On an exposed site that difference may matter more than the headline number.

What we don't know

22 of 45 fields are still unresearched, and fields marked not published mean the manufacturer does not state them — that is a finding about the product, not a gap in our research.

Every figure above links to the document it came from. We have not tested this greenhouse. Local wind, snow, permitting and foundation requirements vary; confirm anything that matters with the manufacturer and your local building authority before buying.

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