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2′ x 4′ mini Garden Cold Frame
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Raised Bed Cold Frame
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What are cold frames?
Put simply, a cold frame (sometimes called a cold frame greenhouse) is a bottomless box that is placed directly onto the soil or a raised bed.
The glass roofs of cold frames should be angled towards the sun in order to capture as much light as possible. Typically, the temperature inside a garden cold frame is between 5 and 10 degrees warmer than the outside environment.
This difference in temperature means gardeners can extend the growing season by a few valuable weeks, while protecting plants and seedlings from high winds, heavy rainfall, snow and freezing conditions.
In the spring, cold frames can also be used to house tender young plants, acting as an intermediary stage between the warm conditions of a greenhouse and the cooler environment of a garden.
If you’re a keen vegetable gardener, placing a cold frame directly onto your veg patch warms up the soil to enable early planting, at the same time providing protection from wind, rain and bugs.
Features of our Cold Frames
Our Cold Frames are unique. Originally designed in the late 1950’s for commercial market gardeners, the Cold Frames combine easy access into the frame with superb ventilation – both the side and the roof panels all slide or can be removed for ventilation.
Unlike traditional Cold Frames, there are no lifting lids to catch the wind and the real glass (safety glass of course!) gives the frame weight to keep it on the ground – ideal for coastal and moorland locations.
Benefits of our Cold Frames
Discover the unique features of our cold frames, which distinguish them from other cold frames for sale.
- Easy access – with a sliding roof and side panels, gaining access to our cold frames is extremely easy. For even more accessibility, the panels can even be lifted out completely.
- Superior ventilation – sliding panels also mean better ventilation. On cooler days, opening a panel slightly can help prevent diseases associated with moist or stagnant air, while in the summer heat the panels can be wide open.
- Windproof – as our cold frames are fully glazed using toughened safety glass, their substantial weight will prevent them from blowing away, even in storm force winds. Their strong aluminium framework also comes with a 25 year guarantee.
- Moveable frame – although the glass makes our cold frames heavy, once the panels have been removed, the aluminium framework can be lifted easily. This allows the earth to be dug over or the cold frames to be moved from place to place.
- Quality glass – while plastic scratches easily, attracts dirt, degrades in sunlight and can bow in the wind, our glass panels are strong and rigid. They’re also easy to clean with excellent light transmission, reflecting heat radiated from within back into the cold frame.
- Removable roof panels – the top panels on our cold frames can be removed in late spring to allow taller plants to grow out through the roof and rain to enter. With the side panels still in place, the soil remains warm and plants are protected from the wind.
When to use cold frames
Each season of the year is unique in its own way, each bringing its own challenges too. With one, or even more, of our cold frames, it’s easy to extend the growing season of your favourite plants, herbs, fruits and vegetables.
Spring
As a halfway house between the greenhouse and cooler garden conditions, cold frames are a handy place to harden off tender young plants, including those unable to withstand a wet, cold and frosty winter.
In February and March, use cold frames for an early sowing of broad beans, sweet peas and lettuce, then from April to June fill it with hardy annuals, half-hardies, plants for the veg patch and tender bedding.
Summer
Encourage a larger crop and quicker ripening by using your cold frame greenhouse to provide extra warmth for tender summer crops like tomatoes, aubergines and chillies.
Cold frames can also be used to sow biennials, such as stocks and sweet williams, for next spring. Sow into seed trays in your cold frame for added protection.
Autumn
Use your cold frame at this time to protect cuttings and young plants from the cooler weather and the milder of the first frosts.
By September, they can become home to autumn-sown hardy annuals, which will happily overwinter here.
An autumn sowing of pea shoots, winter lettuce and oriental leaves in planters will give you salads right up to Christmas. In the autumn, you can also grow larger vegetables in a cold frame, including carrots and leeks.
Winter
Cold frames really do come into their own in winter. Plants that don’t like sitting in wet compost over winter, such as succulents and some herbs, can be kept dry in a garden cold frame.
If propagating plants is your thing, cold frames are a feasible alternative to a greenhouse for storing cuttings through the year. You can also overwinter young annuals and sow seeds for salad greens for a harvest in March.
While most alpines are perfectly happy in the cold of winter, they do not like the wet, which can cause them to rot. Placing your alpines in a cold frame will give them the airflow they need while protecting them from the rain.
The best spot for cold frames
As cold frames are passive solar collectors, and are designed to capture heat, the best place to position them is usually somewhere that offers full sunshine, but also some shelter.
In the UK and the rest of the northern hemisphere, that means the sloping top is best positioned to face south, southeast, or southwest. This allows the maximum amount of sunlight to enter the sunlight into the cold frame greenhouse during winter, when the sun travels lower in the sky.
If you’re sowing or planting directly into the ground, it will obviously be put on top of your chosen bit of soil. However, if you use your cold frames mostly for growing cuttings, it would be better to put them somewhere shady.
Cold frame accessories and spares
We’ve a wide range of cold frame accessories you could add to your cold frames, including shade covers to reduce the amount of light entering the cold frame and louvre vents to increase the level of ventilation in your garden cold frame.
We’ve also seed tray shelves and shelf covers in a variety of sizes, plus mist watering equipment and heaters. And, to reduce the amount of bending you have to do when gardening, we’ve a sustainably-sourced, three-tier timber base to raise the height of our cold frames.
As for cold frame spares, there are channel liners, handles for roof and side panels and replacement glass. Although for peace of mind, you could take out our two-year accidental glass breakage cover.
All our cold frames can be colour coated in a choice of seven attractive shades.
FAQs
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What can I grow in a cold frame?
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Can you start seeds in a cold frame?
Cold frames are the ideal place to sow early spring seeds, either directly into the soil beneath your garden cold frame or in seed trays.
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How tall should a cold frame be?
Ideally, the height of your cold frame greenhouse should be slightly taller than the height of the plants you’re growing inside when they reach maturity.
The great thing about our frames is that the glass roof sections can be removed to allow taller plants to grow out through the top.
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How do you keep a cold frame warm at night?
In general, cold frames require little or no protection at night. However, if snow or frost are forecast, you could place an waterproof insulated blanket/tarp over the frame.
Alternatively, you can cover your plants with a layer of horticultural fleece, which will help retain heat from the soil. Or you can fill three or four large plastic drinks bottles with very hot water and place them in the cold frame, then cover the frame with a heavy blanket.
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Why use a cold frame?
Cold frames are an ideal environment in which to raise cuttings, sow seeds and protect young or tender plants before they are planted in a garden. They are also a practical alternative to greenhouses if you lack the space.
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Do cold frames protect plants from frost?
Garden cold frames will protect young plants and cuttings from the first frosts of autumn, but not the severe frosts later in the year.
From mid autumn and through winter, on cold nights a waterproof insulated blanket/tarp can be placed over the top to provide some insulation against frosts. But remember that this will reduce the amount of light and ventilation getting into the cold frame, so should be removed in the morning.
Alternatively, you can cover your plants with a layer of horticultural fleece, which will help retain heat from the soil.
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Does a cold frame need to be in the sun?
The whole idea behind cold frames is that they offer ideal growing conditions by capturing the heat of the sun. So yes, cold frames should be placed where they have maximum exposure to sunlight.
In the UK, this means placing the sloping top of your garden frame so that it faces south. If this is not possible, southeast, or southwest or good alternative positions.
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What’s the difference between a cold frame and a greenhouse?
The main difference between a cold frame and a greenhouse is that cold frames are not heated, relying instead on heat from the sun. Of course, with most standing just a few feet tall, they are much smaller than greenhouses.
However, just like a greenhouse, cold frames can be ventilated. This can be done by sliding open the top or sides panels, or fitting an automatic louvre system to your garden cold frame.
Cold Frames make an ideal companion to a large greenhouse, as they provide a hardening-off area for plants coming out of the greenhouse that are not quite ready for the outdoors.
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What direction should a cold frame face?
The ideal spot is in a position where its sloping top is facing south. This is because cold frames work by capturing the heat of the sun, and south-facing is where it will get the most sunlight during the day.
However, not garden is ideal, so as long as the Cold Frame gets some sun, or at least plenty of ambient light, it will provide a good growing environment for the plants.
How can we help?
We hope you’re now aware of the many benefits of our aluminium cold frames, particularly as an ideal accessory to your greenhouse.
If you have any questions or need some further gardening advice about our cold frames, please contact us by calling 01788 822 301 or emailing [email protected].
