Sigma Small Greenhouse

Compact Backyard Kits, 6.5 ft Wide

4.7 · 90 reviews
Save $300
Sigma 200 (Gen III) greenhouse with transparent panels on a grassy area in front of a house.
Sigma 2x6 (Gen III) greenhouse in a field with trees and sky in the background by Planta Greenhouses EU.
Sigma 200 (Gen III) Greenhouse interior with soil floor and glass walls, outside view of grassy field.
Interior of a Sigma 200 (Gen III) greenhouse with shelves and a ladder.
Metallic door with a handle and key lock on a Sigma 200 (Gen III) greenhouse door.
Clear polycarbonate Sigma 200 (Gen III) greenhouse structure with metal frame in a warehouse setting
Partial view of a Sigma 200 (Gen III) greenhouse with transparent panels and metal frame.
Partial view of a Sigma 200 (Gen III) greenhouse with a sliding door
Metal Sigma 200 (Gen III) greenhouse structure with curved roof and transparent panels on a concrete floor.
Interior of a Sigma 20 (Gen III) greenhouse with transparent walls and a door.
Modern Sigma 200 (Gen III) greenhouse with transparent walls and a curved roof in a garden setting - by Planta Greenhouses EU.
Clear Sigma 200 (Gen III) greenhouse with open door in a garden setting - by Planta Greenhouses EU.

Sigma Small 20

Sigma Small greenhouse kits are arched backyard greenhouses rated for 4.5 ft (55 psf) of snow and 65 mph wind, with 6 mm twin-wall polycarbonate panels and a 10-year warranty. They're for sale in 5 sizes, all 6.5 ft wide, so you can choose the length that fits your space. Find your greenhouse.

Size: Sigma Small 20 · 6.5′ × 20′Size guide
$3,800$4,100Save $300

Free shippingTo nearest terminal
10-year warrantyFrame & panels
Pre-cut panelsFor easier installation
Guided assemblyVideos and live chat
Questions? Talk to a grower.

Mon–Fri 9am–5pm EST or Send a Message

Call us1-877-669-1286

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Which size is best for your garden?

Get this sizing guide with photos and bed layouts.

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  • Insulated Doors NEW – Helps reduce heat loss and drafts, creating a more stable growing environment and improving energy efficiency.
  • Upgraded Door Handles NEW – Smooth, reliable operation with a sturdy grip for easier daily access and long-term durability.
  • Aluminum Polycarbonate Trim NEW – Securely locks panels in place along the arch for added strength, better weather resistance, and a clean, finished look.
  • Window/Door Latch NEW - Makes the door and window open together.
  • Improved Snow Load [NEW] - Rated for a snow load of up to 55 psf (about 4.5 ft of snow).
  • Wind resistant up to 65 mph for those living in gusty climates.
  • Comes with two doors (one at each end).
  • Made with a heavy-duty galvanized steel frame and 6 mm twin-wall polycarbonate panels.
  • Arched shape - helps wind, snow and hail slide off the sides.
  • Extendable beyond 100 ft - so you can expand your greenhouse when you're ready.
  • Maintenance-free means you have more time to focus on your garden.
  • We offer a 10-year warranty because our greenhouse is heavy-duty and long-lasting.
  • Access to our private Facebook group to connect with and learn from other greenhouse owners.
  • The Sigma Small Greenhouse is available in 5 size configurations. Plus, you may purchase an extension kit, to extend the length of the greenhouse.
  • Extendable & Customizable
  • Snow Load Up To 55 psf 
  • Wind Resistant up to 65 mph
  • We offer a 10-year warranty because our greenhouse is heavy-duty and long-lasting.

Planta Greenhouses se dedica a entregar su pedido rápidamente, para que pueda comenzar a utilizar sus productos de invernadero de inmediato.

Debido a que los invernaderos se empaquetan en cajas grandes, tienen requisitos de envío únicos, que incluyen:

  • Nos comunicaremos con usted para confirmar el precio de envío, según su ubicación y el tamaño del pedido.
  • El envío para la mayoría de los pedidos cuesta entre $250 y $450. Las entregas a zonas remotas pueden tener un costo adicional.
  • Al realizar su pedido, asegúrese de introducir el teléfono y la dirección correctos al finalizar la compra. Nos pondremos en contacto con usted por teléfono antes del envío. No nos responsabilizamos de entregas a direcciones incorrectas.
  • Como parte del proceso de entrega, necesitamos un número de teléfono localizable (para que la empresa de mensajería se comunique con usted) antes de enviar el artículo.
  • Haremos todo lo posible para enviar su pedido lo más rápido posible y mediante el medio de transporte que usted especifique. Sin embargo, si no hay instrucciones específicas, aplicaremos nuestro criterio y realizaremos el envío de la manera más rápida y económica. No nos responsabilizamos por retrasos en la entrega debidos a circunstancias ajenas a nuestra voluntad.
  • No realizamos envíos a apartados postales, ya que en la mayoría de los casos deberá firmar para recibir su artículo.
  • No disponemos de servicio de entrega urgente. Los componentes del invernadero se entregan en varias cajas, la más grande de las cuales pesa 36 kg. El invernadero se entregará en la entrada de su casa. Por favor, coordine el traslado del paquete a su ubicación de instalación.
  • Los pedidos realizados los fines de semana y días festivos se procesarán el siguiente día hábil.
Free guide

The Beginner's Guide for Greenhouse Owners

Tell us where to send it and it's yours.

Compare Sigma Small Greenhouse Sizes

This greenhouse comes in several size configurations. Every greenhouse extends in 6.5 ft sections, so pick the length that fits your plot and your plans.
Arch-shaped Sigma 2x4 (Gen III) greenhouse in a garden with flowers and a stone path by Planta Greenhouses EU. Sigma Small Compact
6.5′ × 6.5′
Clear Sigma 200 (Gen III) greenhouse with open door in a garden setting - by Planta Greenhouses EU. Sigma Small Urban
6.5′ × 13′
Sigma 200 (Gen III) greenhouse with transparent panels on a grassy area in front of a house. Sigma Small 20
6.5′ × 20′
Sigma 2x8 (Gen III) greenhouse with a curved glass roof and walls on a grassy area. Sigma Small 26
6.5′ × 26′
Sigma Small Greenhouse Sigma Small 32
6.5′ × 32′
Price
Sale$2,500
$2,400
Sale$3,250
$3,050
Sale$4,100
$3,800
Sale$4,950
$4,550
Sale$5,800
$5,300
About
Starter size: shelves or a bed on one side for greens, herbs and seedlings.
A bed along one side and shelving on the other for seedlings and herbs.
Room for a long bed, a few tomato plants and a potting shelf.
Long beds for greens and tall crops, with a narrow center path.
The largest Sigma Small: a long growing space for beds, shelving and climbing crops.
Width
6.5 ft
6.5 ft
6.5 ft
6.5 ft
6.5 ft
Length
6.5 ft
13 ft
20 ft
26 ft
32 ft
Height
8 ft
8 ft
8 ft
8 ft
8 ft
Sq ft
42 sq ft
85 sq ft
130 sq ft
169 sq ft
208 sq ft
Owner reviews
4.7 Read all 90 reviews
Read all 90 reviews
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Dome-shaped Greenhouse
About this model

Dome-shaped Greenhouse

Sigma greenhouse has a dome-shaped arch which sheds snow and rain, and the galvanized steel frame with 6 mm twin-wall panels is rated for 55 psf of snow. Insulated doors help keep the warmth in.

pg why planta
Why Planta Greenhouses

Winter-Ready Greenhouses

Heavy-duty greenhouses used by 25,000+ growers since 2019, designed to withstand heavy winters. Backed by a 10-year warranty and live customer support.

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Shipping & assembly

Arrives in labeled boxes

Free shipping to the closest terminal in the lower 48. Every panel is pre-cut and every bag of hardware is labeled, so two people can build it with the step-by-step videos.

Questions? Talk to a grower.

Mon–Fri 9am–5pm EST or Send a Message

Call us 1-877-669-1286