Planta Greenhouses vs. Riga Greenhouses: Which Greenhouse Is Better for Your Climate & Garden Goals?

Planta Greenhouses is renowned for its European design heritage and commitment to durable, all‑weather structures. Rather than light DIY kits, Planta Greenhouses builds its greenhouses with galvanized steel frames and thick polycarbonate panels so growers can cultivate crops through frost, rain, and heavy snow.

Two best‑selling models illustrate the brand’s philosophy:

• Planta Greenhouses Sungrow 20:  A greenhouse engineered for extreme winter conditions, designed to handle deep snow and gusty winds.
• Planta Greenhouses Sigma 20: A slightly smaller and less expensive yet still rugged enough for serious gardeners in temperate climates.

These models show why Planta Greenhouses markets itself as premium but attainable: they combine industrial‑grade materials, high snow‑load ratings, and long warranties while remaining within reach for dedicated home growers.

What This Article Covers

In this guide, you’ll see side‑by‑side evaluations of comparable greenhouses from Planta Greenhouses and Riga Greenhouse Kit. We’ll cover real specifications, key benefits and drawbacks, and clear guidance on which structure suits your climate and gardening style. If you’re curious about Planta vs. Riga, keep reading. This comparison will help you choose with confidence.

Sungrow 20 vs. XL 6 Professional Greenhouse

Comparing Planta Greenhouses Sungrow 20 and Riga XL 6 Professional Greenhouse

Within Riga’s product line, the XL 6 Professional is the closest match to the Sungrow 20 in both footprint and intended use. Each aims to serve year‑round growers who need robust protection from the elements.

Design & Aesthetics

• Planta Greenhouses Sungrow 20: A bell‑shaped tunnel that sheds snow and wind naturally; doors at both ends with optional roof vents for cross‑flow; modern galvanized‑steel look.
• Riga XL 6 Professional Greenhouse: A rounded “onion” shape with no eaves for superior wind and snow shedding; two Dutch doors and four automatic roof vents.

Build Materials

• Planta Greenhouses Sungrow 20: A galvanized‑steel frame plus 6 mm double‑wall polycarbonate (10 mm upgrades available).
• Riga XL 6 Professional Greenhouse: An aluminum frame with 16 mm triple‑wall polycarbonate sides and 16 mm twin‑wall ends.
• Learn Which Greenhouse Frame is Better - Galvanized or Aluminium?

Climate Resistance

• Planta Greenhouses Sungrow 20: Designed for harsh climates with a snow‑load capacity of 75 psf (≈ six feet of light snow or three feet of packed snow); rated to withstand winds up to 65 mph.
• Riga XL 6 Professional Greenhouse: Not rated in psf, but the onion profile has been tested to 100 mph winds and naturally sheds snow.

DIY Friendliness & Installation

• Planta Greenhouses Sungrow 20: An intermediate build; heavier steel means two to three people recommended; no concrete foundation required.
• Riga XL 6 Professional Greenhouse: An assembly requires two–three people and about two days; base frame strongly recommended.
• Explore 5 Tips to Make Your Greenhouse Installation Easy

Price‑to‑Performance Value

• Planta Greenhouses Sungrow 20: Priced around US $3,600–$3,900 with a 10‑year manufacturer’s warranty.
• Riga XL 6 Professional Greenhouse: Costs roughly US $15,000–$16,000; the higher cost reflects triple‑wall glazing and extra height.

Year‑Round Growing Capabilities

• Planta Greenhouses Sungrow 20: Double‑wall insulation improves heat retention for winter crops.
• Riga XL 6 Professional Greenhouse: Thicker panels and multiple automatic vents provide excellent insulation and ventilation.

Post‑Purchase Support

• Planta Greenhouses Sungrow 20: Backed by a 10‑year warranty and a responsive support team, owners can join the Planta Greenhouses Community for shared experiences.
• Riga XL 6 Professional Greenhouse: Offers a 10‑year prorated panel warranty and 15‑year frame warranty.

Key Differences: Sungrow 20 vs. XL 6 Professional

Why Choose Planta Greenhouses Sungrow 20?

If your climate is unforgiving or you simply want a fortress‑like greenhouse, the Sungrow 20 is a smart pick. Its galvanized‑steel structure and thick polycarbonate panels shrug off heavy snow and gusty winds. The 10‑year warranty and modular design add long‑term value, and you can expand as your gardening ambitions grow. 

For more inspiration, visit the Sungrow Greenhouses Collection.

Why Choose Riga XL 6 Professional Greenhouse?

The Riga XL 6 Professional appeals to gardeners seeking ultimate strength and insulation. Its aluminum frame with triple‑wall polycarbonate panels, curved “onion” design and 100 mph wind rating provide a commercial‑grade environment. You also get multiple automated roof vents, wide Dutch doors and a 15‑year frame warranty.

👉 See current offers for the Riga XL 6 Greenhouse on Amazon

Sigma 20 vs. IV 9×14 (Premium Package)

Comparing Planta Greenhouses Sigma 20 vs. Riga IV 9×14 Greenhouse (Premium Package)

Looking for something smaller or more budget‑friendly? The Sigma 20 might suit you better. Riga’s IV 9×14 Premium is its closest competitor from Riga Greenhouses.

Design & Aesthetics

• Planta Greenhouses Sigma 20: A continuous tunnel arc encourages airflow and even sunlight; doors and vents are at both ends.
• Riga IV 9×14 Greenhouse:

  An onion‑shaped greenhouse with a single barn‑style door and two automatic roof vents; classic European look.

Build Materials

• Planta Greenhouses Sigma 20: A galvanized pipe‑steel frame with 6 mm double‑wall polycarbonate.
• Riga IV 9×14 Greenhouse:

  An aluminum frame; 8 mm twin‑wall polycarbonate on the sides and 10 mm on the ends.

Climate Resistance

• Planta Greenhouses Sigma 20: Rated for a 32 psf snow load and winds up to 65 mph.
• Riga IV 9×14 Greenhouse: Not specified in psf, but the onion profile has been tested against 100 mph winds and sheds snow effectively.
• Learn what snow load (PSF) means for your greenhouse

DIY Friendliness & Installation

• Planta Greenhouses Sigma 20: An intermediate difficulty; modular sections mean you can lengthen it easily.
• Riga IV 9×14 Greenhouse:  

  An assembly for two people; includes base frame and shelves but no expansion capability.

Price‑to‑Performance Value

• Planta Greenhouses Sigma 20: Typically around US $3,050, offering robust construction at an accessible price.
• Riga IV 9×14 Greenhouse:

  About US $9,209; price includes extras but provides less growing space.

Year‑Round Growing Capabilities

• Planta Greenhouses Sigma 20: Double‑wall panels keep temperatures stable through the seasons.
• Riga IV 9×14 Greenhouse:

  Thicker panels offer good insulation; automatic vents help regulate heat.

Post‑Purchase Support

• Planta Greenhouses Sigma 20: A 5‑year warranty and responsive customer service give owners confidence.
• Riga IV 9×14 Greenhouse:

  includes a 10‑year panel warranty and 15‑year frame warranty.

Key Differences: Sigma 20 vs. IV 9×14 (Premium Package)

Why Choose Planta Greenhouses Sigma 20?

The Planta Greenhouse Sigma 20 is ideal for gardeners wanting a durable yet budget‑friendly greenhouse. Its galvanized-steel frame and double-wall polycarbonate stand up to winter weather, while the curved design distributes light evenly and allows for good airflow. Because it’s modular, you can lengthen the structure as your garden expands. At roughly $3,050, it offers a lot of greenhouse for the money.

Explore the Sigma Greenhouses Collection

Why Choose Riga IV 9×14 Greenhouse?

The Riga IV 9×14 Premium is perfect for gardeners who want a compact yet powerful greenhouse with classic European charm. It combines an aluminum frame with thicker 8 mm and 10 mm polycarbonate, providing excellent insulation and long-term durability. The automatic roof vents, large rear window and barn‑style door ensure good ventilation while maintaining warmth.

👉 See current offers for the Riga IV 9×14 Greenhouse on Amazon