Best Greenhouses & Cold Frames — Plastic (2026)
6 greenhouses & cold frames matching material “Plastic”, hand-picked from UK Amazon listings.
Not sure which one to pick? Read our Best Greenhouse UK (2026) guide.
£19.99
Pros
- Reinforced weatherproof PVC cover
- Roll-up zip door for easy access
- Tool-free assembly, ideal for patios
Cons
- Less sturdy than a full-size greenhouse
- Cover needs replacing after a few seasons
#2 Pick
Outsunny Polytunnel Greenhouse with Windows and Door, 3 x 2m- Plastic
- Large gardens
- 1 Year
£56.99
Pros
- Galvanised steel frame for durability
- Roll-up door and mesh windows for ventilation
- Walk-in height suits full-size crops
Cons
- PE cover less durable than polycarbonate or glass long-term
#3 Pick
Oypla Growbag Tomato Growhouse Garden Greenhouse with PVC Cover, 150x100x50cm- Plastic
- Balcony/patio
- 1 Year
Currently unavailable
Pros
- Sized to fit standard growbags
- Sturdy tubular steel frame with PVC cover
- Roll-up zipped door for ventilation
Cons
- Best suited to patios rather than full-size crops
£45.00
Pros
- Compact 4-tier design suits patios and balconies
- Clear PVC cover lets in plenty of light
- Roll-up door for easy access and ventilation
Cons
- Lightweight frame less stable in strong winds
#5 Pick
Palram Canopia EcoGrow 6x8 Greenhouse, Green- Plastic
- Small gardens
- 1 Year
Currently unavailable
Pros
- Affordable entry point into full-size greenhouses
- Resin frame resists rust and rot
- Reinforced polyethylene cover lets in plenty of light
Cons
- Cover less durable long-term than polycarbonate or glass
#6 Pick
Gardman 4 Tier Mini Greenhouse Shelving Unit- Plastic
- Seed Starting
- 1 year
Currently unavailable
Pros
- Four deep shelves for pots and seed trays
- No-tool push-fit steel frame assembly
- Roll-up zippered door for easy access
Cons
- PE cover is less durable than polycarbonate panels
At a glance
- Products
- 6
- Price range
- £19.99–£99.99
- Average price
- £47.65
- Average rating
- 4.18 / 5
- Total reviews
- 5,428
- Top brand
- Gardman (2)
- Price tier split
- Budget4Mid-range2Premium0
- In stock
- 3
Plastic greenhouses and cold frames provide a straightforward solution for extending the growing season and protecting tender plants. These structures are constructed primarily from durable, lightweight plastic sheeting, offering excellent insulation against frost and reducing temperature fluctuations within the frame. Ideal for beginners or those seeking an affordable and easy-to-assemble option, plastic greenhouses can be set up quickly to create a sheltered environment for seedlings and young plants – perfect for extending your gardening year. They're particularly useful for starting vegetables like tomatoes and peppers early on, or protecting delicate herbs from late spring frosts.
When choosing a plastic greenhouse, consider the size you require based on the types of plants you intend to grow and the available space in your garden. Many models come with clear PVC or polyethylene sheeting, providing optimal light transmission for plant growth. Remember that while these frames offer significant protection, they may not withstand extremely high winds; securing them properly is essential for stability.
These plastic cold frames are frequently used as extensions to existing gardens, creating a mini-environment ideal for hardening off tender plants before transplanting outdoors or for overwintering hardy varieties. Amazon UK offers a wide selection of sizes and styles, ranging from small individual units to larger structures suitable for multiple plants – ensuring you can find the perfect solution to suit your needs.
FAQ
What is the typical lifespan of a plastic greenhouse?
The longevity of a plastic greenhouse depends largely on usage and weather conditions. PVC sheeting generally lasts 3-7 years with reasonable care, while polyethylene can degrade more quickly due to UV exposure – expect around 1-3 years for this material. Regular cleaning and protection from extreme temperatures will extend the lifespan.
How do I secure a plastic greenhouse in windy conditions?
Most plastic greenhouses include fixings like ground stakes or straps. For added stability, consider using sandbags to weigh down the base or anchoring the frame with wooden posts driven into the ground – ensuring they’re securely fastened.
What type of flooring is suitable for a plastic greenhouse?
A simple gravel layer provides good drainage and prevents moisture build-up. Alternatively, a thin rubber mat can protect plants from damage and reduce weed growth; avoid using wood directly as it can rot quickly.
Do I need to vent my plastic greenhouse?
Ventilation is crucial for maintaining healthy plant growth within a plastic greenhouse. Regularly opening vents allows excess heat and humidity to escape, preventing condensation build-up and reducing the risk of fungal diseases – aim for several times daily.
What’s the best way to clean a plastic greenhouse?
Use warm soapy water and a soft brush or cloth to gently scrub away dirt and debris. Avoid using harsh chemicals that could damage the plastic sheeting; rinsing thoroughly with clean water is important afterwards.
Can I use plastic cold frames indoors?
Yes, small plastic cold frames are perfect for starting seeds indoors. They provide a controlled environment, maintaining consistent warmth and humidity until seedlings are ready to be transplanted into your garden – ensure adequate ventilation.
How do I store my plastic greenhouse during the winter?
Ideally, store it in a dry place away from direct sunlight and extreme temperatures. If space is limited, cover the frame with a protective cloth to shield it from the elements; consider dismantling smaller units for easier storage.
What’s the difference between PVC and polyethylene plastic greenhouses?
PVC (Polyvinyl Chloride) sheeting is more durable and resistant to UV degradation than standard polyethylene. However, it’s typically more expensive. Polyethylene is lighter and often more affordable but requires more frequent replacement due to its lower resistance to sunlight.
Are plastic greenhouses suitable for growing tomatoes?
Absolutely! Tomatoes thrive in the controlled environment of a plastic greenhouse, allowing you to start them on early in the season and protect them from late frosts. Ensure adequate ventilation and support for developing tomato plants as they grow.
How do I maintain temperature inside my plastic greenhouse?
Maintaining optimal temperatures involves careful monitoring and adjustments. Use thermal curtains or blankets during cold nights to retain heat, and remove them during warmer days to prevent overheating; consider a small electric heater if necessary for extra warmth.