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Cold frames

cold frame gardening

Buy a cold frame for vulnerable seedlings

Transform your gardening experience with our top-quality cold frames, crafted from high-grade aluminum frames and twin-wall polycarbonate sheets. These innovative structures provide exceptional protection and support for your vulnerable seedlings, helping them thrive and elevate your garden's productivity.

A cold frame to last for days to come

With our cold frames, you're not just buying a product but investing in the ideal environment for your plants to thrive year-round. Our commitment to quality ensures that you receive a durable and cost-effective solution for your gardening needs. Whether you're a seasoned gardener or a green-thumbed beginner, our mini greenhouses create the perfect conditions for a diverse range of fruits and vegetables, regardless of the season.

What is a cold frame?

A cold frame is a transparent enclosure designed to harness sunlight and create a microclimate for plants. Bigger than a cloche, but smaller than a mini greenhouse, a cold frame extends the growing season by shielding plants from harsh weather conditions. Its versatility allows you to control temperature and humidity, providing an optimal environment for seed germination, hardening off seedlings, and nurturing robust plants throughout the year.

open cold frame

Gardening with a cold frame

Cold frame gardening can help you increase your yields and explore more plant varieties, including tender plants like eggplants and chilies. Our standalone cold frames offer ample space and protection for young crops to grow, providing 33 cm of clearance at the front and 44 cm at the rear. This makes them perfect for nurturing young plants and overwintering hardy vegetables, ensuring they thrive in various weather conditions.

planting cold frame

What to grow in a cold frame

Maximize the potential of your cold frame by choosing the best cold frame plants. Shield alpines from excessive rain, preserving their delicate beauty. Extend the life cycle of young annuals by overwintering them. Elevate your summer harvest by cultivating heat-loving crops like eggplants, tomatoes, and chillies, utilizing the box's warmth to boost yields. Harden off tender young plants and vegetables gradually, transitioning them from indoor environments to harsher outdoor conditions over 2-3 weeks. Gain a head start on the growing season by planting early crops like spinach, radishes, or peas, taking advantage of the protective environment the cold frame offers

Hardening off seedlings in a cold frame

The most important aspect of hardening off seedlings in a cold frame is ensuring the plants can gradually acclimate to colder conditions. This typically takes 2-3 weeks, allowing the plants to adjust to temperature variations, increased sunlight, and potential wind exposure. If particularly cold temperatures are expected overnight, throw old blankets over the growhouse.

    Four helpful tips for using a cold frame

    • Temperature Monitoring

      Regularly check and adjust the internal temperature of your cold frame to ensure it aligns with your plants' specific needs. Use a thermometer to maintain optimal growing conditions.

    • Ventilation

      Proper airflow is key. Avoid overheating by strategically opening the cold frame on warmer days. Conversely, secure it during colder nights to retain warmth. This balance promotes a healthy environment for your plants.

    • Watering Strategy

      Be mindful of watering frequency. Coldframes can limit natural rainfall, so a consistent watering schedule is essential. However, proper drainage should be ensured to prevent waterlogging and root issues.

    • Seasonal Adaptation

      Tailor your cold frame gardening approach to each season. Use the frame to start seeds in spring, protect plants from summer heat, extend the growing season in autumn, and provide winter shelter for cold-tolerant crops. Adapting to seasonal nuances maximizes the benefits of your growhouse.

    Choosing between a cold frame, greenhouse or polytunnel

    cold frame gardening

    Cold Frames

    • Small, low to the ground, portable
    • Polycarbonate panels, aluminium frame
    • Low cost
    • Simple & quick setup
    • Limited climate control
    To the cold frames
    small greenhouse gardening

    Mini Greenhouses

    • Walk-in, more permanent
    • Polycarbonate panels, aluminium frame
    • Pricier, depending on the size
    • Requires more time and effort to setup
    • Great climate control with skylights
    To the greenhouses
    polytunnel gardening

    Polytunnels

    • Tunnel-shaped, semi-permanent
    • Polythene plastic cover, steel frame
    • Medium to high cost, depending on size
    • Moderately easy to setup
    • Great climate control with oll up windows
    To the polytunnels

    The best materials for a cold frame

    Our cold frame covers are crafted from high-grade aluminium and twin-wall polycarbonate sheets, which ensure long-life protection and insulation for your plants.

    Twin-wall polycarbonate cold frames

    Our professional garden greenhouse cold frame has a polycarbonate cover and walls. This lightweight, hard-wearing material has excellent properties that meet the requirements of growing both tender and half-hardy plants:

    • Thermal Insulation

      The polycarbonate panels provide thermal insulation, maintaining a stable and warm environment for plants during colder months, ensuring their growth and survival.

    • UV Protection

      The polycarbonate material effectively filters harmful UV rays, protecting the plants from potential sun damage while still allowing them to thrive under natural light.

    • Light Transmission

      The 16-mm-thick twin-walled polycarbonate panels allow optimal light transmission. This ensures that plants receive adequate sunlight for photosynthesis, promoting healthy growth.

    Strong and lightweight aluminium frames

    The aluminium used in our cold frames boasts exceptional durability, providing a sturdy foundation for long-lasting structures. Its corrosion-resistant properties make it an ideal choice for metal cold frames, ensuring longevity in various weather conditions. Crafted with precision, our aluminium cold frames offer robust support while maintaining a sleek and lightweight design for ease of use.

    aluminium cold frame

    Comparison of various cold frame materials

    Woodern cold frame with glass coverAluminium cold frame with polycarbonate panels
    Natural material
    Durable and weather-resistant
    Rustic look
    Clean modern appearance
    Not weather-resistant
    Lightweight and easy to handle
    Bulky timber frame
    Easy access with hinged lids
    Needs care & maintenance
    10 year guarantee on the polycarbonate sheets

    How to build a cold frame

    Homemade cold frames are a big hit with amateur gardeners. Making your own garden frame is the ideal way to start gardening under cover, and has its advantages. On the other hand, DIY cold frames are often made of wood or glass, materials that don't offer the best properties for practical long-term use.

    As well as being easy to assemble, our polycarbonate mini greenhouse will ensure that your vegetable garden grows and is protected for years to come. Our models are delivered in kit form with all the components you need for self assembly, so you're guaranteed to save time!

    Raised bed covers

    Exlpore our assoritment of cold frame attachments for raised beds! We offer cold frame attachments that are measured to fit perfectly on top of our raised garden beds. If

    Our expert service

    Our team of garden experts are happy to be contacted. You can pose them any questions you might have about the relative advantages of aluminium cold frames over wooden ones. Or simply ask about differences in the costs and benefits of coldframes in relation to greenhouses. You can contact us either by phone or email.

    Expert advice

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