Cold Frames

Cold frames protect your plants, seedlings and sensitive greenery from the cold weather and frosts while insulating and ventilating them. Small, lightweight and hard wearing, cold frames are ideal for any size garden, especially if it’s not big enough to get a full size greenhouse into. Our collapsible cold frame is also extra-large allowing you to get more of your home grown produce into it.

Our cold frames range in size and material from collapsible to aluminium through to double, large and rustic cold frames. So whatever your garden landscape setting is, you'll find the right cold frame here. Wooden cold frames offer good insulation, but are more difficult to move around the garden during the year than the clear frame and aluminium products. Those cold frames with clear sides also let more sunlight in during the day but again don't offer the same insulation as clear sided cold frames. Our premier wooden cold frame comes with a 15 year guarantee and looks great in any garden.

At great prices and with discounts throughout our cold frame product range, you won’t stretch your budget. Remember, all our products are free delivery within the UK, so there’s no additional charge on checkout to have your cold frame delivered straight to your door!

When choosing a cold frame, one of your main considerations should be the type of glazing used in its construction. Polycarbonate is up to 200 times stronger than glass and half its weight. It really is an incredibly strong material.

Polycarbonate is much safer in lower cold frames - especially for the elderly and where children play (or may even climb on them!).

Why risk shards of glass from a stray football or a child falling onto your cold frame?

Horticultural glass is usually 3mm thick and has an 'R' value (thermal insulation rating) of 0.93. Clear single layer polycarbonate is only slightly lower at 0.83 - bubble wrap or fleece over the tenderest plants in the depths of winter more than compensates for this. However 4mm twin wall polycarbonate has an R rating of up to 1.42.

As hot air rises, twin polycarbonate is certainly ideal for the roof of your cold frame

Twin wall poplycarbonate will allow slightly less light through your coldframe, but as it diffuses the light passing through the twin wall, the light will penetrate in areas that would otherwise not be reached - this might be a bonus.

Cold frames were originally designed to sit adjacent to the greenhouse, and unheated cold frames were used to harden off plants and seedlings grown in the heated greenhouse. Usually sited south facing whenever possible, they have always had a roof lid, which allowed the temperature inside the cold frame to be regulated. In past times the glazing would have been glass, but it is rare to find glass glazing now; polycarbonate is many times stronger, allows virtually as much light through, insulates as well, and is so much safer, especially when there are children or pets playing in the garden. They have always been built low to the ground, and protected plants from excessive rain and winds.

Cold frames have been used for many years on vegetable farms and in domestic and stately home gardens. They extend the growing season by creating their own micro-climate, most often used - as they still are today - to harden off seedlings prior to planting into the open ground. Cold frames have also been used over the years to grow vegetables which are resistant to the cold for harvesting late in the year.

The construction of cold frames has changed very little, although in days of austerity old glass windows were used as roof panels, and placed on top of a frame made of any wood which was available. Many today are made of lightweight aluminium which is very long lasting, and can be moved easily if required.

Cold frame design has altered very little over the years, traditionally having a sloping roof which let in the light and could be propped or later hinged open. The sides were usually also glazed, although some older wooden ones you will find had solid wooden walls to give better night time heat retention - not a problem with today's polycarbonate models.

Cold frames are well used to plug the gap between the greenhouse and the open garden and elements. So hardening off of seedlings and bedding plants is a common use. Cold frames protect your plants from night frost, and garden pests, but are you wanting to be a bit more adventurous?

Well you can experiment with seasonal crops for the dinner table. Your low level greenhouse can be used to plant up early spring cropping carrots, spinach, radish, lettuce and winter greens. Try leeks, herbs and salad plants during the warmer months. Choose vegetables that can tolerate the cold if you are using it during the colder months - a cold frame isn't going to produce you vine tomatoes in the winter.

You may want to add extra insulation as protection in the winter months - horticultural bubble wrap is one suggestion.

If you sow salad crops, you can thin them out at intervals, using the thinned out ones as baby leaves on the dinner plate.

If you are growing direct in your cold frame, ensure the compost is weed free - you don't have the luxury of space to give weeds a home. Water thoroughly, and remember to ventilate. As autumn descends close the lid at night, and during the winter give yourself some time off - keep the lid closed most of the time, just opening it a little on a fine winters day for ventilation. Beware of the lid being left wide open when severe winds hit your garden, your cold frame lid is as much at risk then as your house roof tiles!