How Do Planta Greenhouses Compare?

A Side-by-side Comparison of Our Popular Residential Greenhouse Models: The Sigma, Sungrow, and Ministar.

Choosing the perfect DIY greenhouse kit can be incredibly challenging. A slight variation in design, materials or other features can make or break whether or not it will hold up in your climate.

So, how will you know which Planta greenhouse is best for you?

To simplify this process for eager gardeners, we’ve created a side-by-side comparison of our three residential greenhouse models, so you can easily discover which is the ideal choice for you.

Planta Greenhouse Specifications: At a Glance





Materials Galvanized steel frame and 6 mm double-wall polycarbonate panels Galvanized steel frame and 6 mm double-wall polycarbonate panels Galvanized pipe frame and 6 mm double-wall polycarbonate panels
Measurements Height: 83.9in
Length: Varies
Height: 94.5in
Width: 118.1in
Length: Varies
Height: 82.7in
Width: 79in
Length: 130in
Design Arched shape Bell Shape Gable Pointed Shape
Snow Load 3 feet (32 psf) 6 feet (75 psf) 4 feet (240 kg/m2)
Wind Resistance 65 miles per hour 65 miles per hour up to 20m/s
Extension Beyond 100 ft Beyond 100 ft N/A
Warranty 5 years 10 years 5 years



The Planta Sigma, Sungrow, and Ministar Greenhouses are constructed with similar durable materials. They all have 6mm double-wall polycarbonate panels that provide 100% UV protection and will keep your garden safe and secure for years to come. Additionally, the Sigma and Sungrow Greenhouses both have a heavy-duty galvanized steel frame while the Ministar has a galvanized pipe structure.



While the Sigma and Sungrow greenhouses share the same width of 118.1 inches (300cm), their main difference is their height. The Planta Sigma Greenhouse reaches 83.9-inches (213 cm), while the Planta Sungrow Greenhouse boasts a 94.5-inch (240 cm) roof height. Despite the tall design of both DIY greenhouse kits, many of our customers choose to build raised bases to create more room to grow.

When it comes to size, the Ministar is a more compact alternative. The roof height and width sit at 82.7-inches (210 cm) and 79-inches (200 cm) respectively, while the length is a fixed 130-inches (330 cm).



All Planta Greenhouses are created with an emphasis on attractive and functional design. Both the Sigma and Sungrow Greenhouses feature built-in doors and windowson each end, while the Ministar has split doors for easy accessibility and effective air circulation.

However, a significant variation between the three greenhouses is their shape:

  • The Planta Sigma Greenhouse has a smooth curved design that allows the interior to feel wider and more spacious.
  • The Planta Sungrow Greenhouse features a bell-shaped design, allowing the wind, snow, and hail to slide off the sides without causing any damage.
  • The Planta Ministar Greenhouse has a pointed, Gabel roof for a compact and classic design.


Snow Load

One of the key differences between Planta Greenhouses is the snow load.

The Sigma can handle a snow load of up to 3 feet (32 psf), making it perfect for climates such as British Columbia, New Brunswick, and Rhode Island.

The Sungrow is considerably stronger in this area, withstanding a heavy snow load of up to 6 feet (75 psf). While this model is popular across North America, it’s especially well-suited for more extreme climates such as Yukon, Alaska, and Colorado.

Finally, the Ministar can hold a snow load of up to 4 feet (240 kg/m2), making it ideal for areas with moderate winters, such as Nova Scotia and Ontario.


Wind Resistance

The high wind rating is an impressive feature of both the Sigma and Sungrow greenhouses. They’re designed for the gustiest climates, resisting powerful winds up to 65mph (100km).

Additionally, these unmoveable structures can withstand blustery rain, hail, and even the extreme windy challenges of growing in high-altitude climates.

The Ministar may not be as heavy-duty as the Sigma and Sungrow; however, it can still withstand wind speeds up to 20m/s, making it a fantastic option for those living in breezy areas.



Both the Sigma and Sungrow Greenhouses are extendable beyond 100 feet. The length extension kits can expand your DIY backyard greenhouse 6.5 ft at a time and are made out of the same quality materials as your baseline model. This allows for any additional windows, shelves, and much more to be incorporated after the added construction.

The Ministar does not have the option to extend. This model comes in one size and is designed to fit into small spaces.



Extended warranties are included with all Planta Greenhouses. A 5-year warranty is available for the Sigma and Ministar. However, due to the undeniable durability of the Sungrow in the most extreme climates, we offer a 10-year warranty. 


Need Some More Help Deciding?

We understand. Choosing a DIY greenhouse kit is a major decision! That’s why we’ve developed a variety of resources to help gardeners understand every aspect of our greenhouses. Take a look through our detailed articles about planting zones, the benefits of polycarbonate and galvanized steel, how to grow in high-altitude climates, types of greenhouse bases, and much more.

If you still need some assistance determining what greenhouse will work best for your situation, don’t hesitate to reach out to our customer support team. We’d be more than happy to offer some guidance. 

Shop Sigma   Shop Sungrow   Shop Ministar

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