What is a cold frame?
Cold frames are found in home gardens and in vegetable farming. They create microclimates that provide several degrees of air and soil temperature insulation, and shelter from wind. Cold frames are great for beginner gardeners or those with limited space and budget. They’re perfect for extending the growing season and starting seedlings. Greenhouses, however, are ideal for serious gardeners with larger goals.Cold frames create an isolated warm, humid, controlled environment for plants to grow in during the harsher times of the year. A translucent top is angled towards the south in order to capture as much solar radiation as possible throughout the day.What can I use instead of a cold frame? You can use a greenhouse, cloche, hoop house, or grow tunnel as alternatives to a cold frame.To help make a cold frame warm, you should initially place it in the earth, as that will help to insulate the ground in which your plants will grow. Cold frames naturally create a warm and humid environment for your plants to grow in during the colder months.
How to properly use a cold frame?
Ideally, the cold frame is oriented to face south. A southern exposure provides maximum sunlight and heating capacity. To reduce heat loss, position the north end of the structure near a home, garage or fence. For convenience, a nearby water source is helpful. The ideal site for a coldframe is a well-drained soil with a slope facing east or southeast. At the very least the site needs to receive full sun in winter. A coldframe will keep even warmer in winter if it’s snuggled up near a fence, wall, or dense, evergreen shrub on its north side.Cold frames work by trapping heat inside their frame. They are usually built low to the ground and have a transparent lid. Unlike some greenhouses, cold frames are not heated externally and rely on sunlight for warmth.Any reliable heating for a cold frame will need to be electrical. You can use candles, or oil/paraffin heaters, but these aren’t really going to give the same results – and of course they need attention. There are a number of options; soil warming cable, a traditional 100W light bulb, heat mats, or greenhouse heaters.Cold frames with wooden frames are strong and sturdy and tend to provide warmer, more regular temperatures, but the frame will need maintenance to prolong its life. Aluminium cold frames are increasingly popular, being light and long-lasting, but may be expensive.
What is the principle of cold frame?
A cold frame is a glass-topped box that traps heat and humidity; two critical factors when it comes to successfully raising seed and cutting-propagated plants. It essentially extends the season for growing tender plants, seedlings and striking cuttings in cold climates. They are a cheap and easy solution. Starting seeds in a cold frame or greenhouse is a smart and efficient way for gardeners to extend their growing season and ensure healthier, more robust plants. It allows you to get a head start on the growing season, giving your plants a better chance to thrive when they are eventually transplanted into your garden.Cold frames are great for beginner gardeners or those with limited space and budget. They’re perfect for extending the growing season and starting seedlings. Greenhouses, however, are ideal for serious gardeners with larger goals.Unlike a cold frame, a mini greenhouse often has vertical space, making them better suited for growing taller plants, and housing shelves for seedlings or smaller plants.If you haven’t got space for a greenhouse, a cold frame is the best alternative if you which to raise crops of vegetables all year round. Crops such as chard, endive, herbs, leaf lettuce, radishes, salad onions, spinach, small carrots etc are all perfect for growing in a cold frame.More space and height – greenhouses typically provide more space and height compared to cold frames. This allows for the cultivation of larger plants, vertical gardening, and more flexibility in arranging and growing a diverse range of species.
Do cold frames really work?
A cold frame acts like a miniature green house, greatly extending the growing season. You can plant things earlier in the year and keep them growing much later than normal. In areas where it doesn’t get too cold (say, -10C at the lowest) you may even be able to grow heartier plants year-round. A cold frame can be used to harden off your plants. They are protected from cold temperatures during the evening and opening the cold frame allows them to experience outdoor conditions. Know the relative hardiness of your plants. Hardy cool season plants can take temperatures in the 40’s.The beauty of a cold frame is that you can continue to grow overwintering plants and crops. Parsnips, leeks, kale, cabbage – even hardy lettuces, such as lamb’s leaf and claytonia – can be grown long into the winter when protected from the frost.Pack the cold frame tightly with pots, and add leaves or mulch over the soil surface and into any significant air gaps. Make sure all the pots are well watered. Once you have your tender plants stored in a cold frame, you will need to control the weather conditions to maintain a healthy dormancy.Cold Frames A cold frame is a simple unheated structure that provides protection for plants from wind, and cold spring or fall temperatures, moderating air temperatures by 5 to 10 degrees or more. Even though the temperature difference is small, there are times when a few degrees can prevent plant death.Cold frames are typically used for cold-hardy plants that need protection from frost and severe temperatures near the beginning or end of season. You can sow seeds directly into a cold frame weeks earlier than the surrounding garden beds. In the same way, you can keep your plants alive 2 to 4 weeks longer in the fall.
How much does a cold frame increase temperature?
The temperature difference between the inside and outside of the frame is generally not more than 5 to 10 degrees. Cold frames allow plants to be started earlier in the spring and survive longer into fall and winter. Water plants early in the day so the foliage has time to dry before the frame is closed. Only water the plants when they are dry. For transplanted or direct sown plants, very little water is necessary since the cold frame retains moisture and temperatures are still cool.