When the
cold frame is open, the roll-top is out of the way, which allows the rain to come in.
Gardeners in cold regions--Zone 6 or less--can boost temperatures inside their frames by adding thermal mass to the interiors (see "Boost Thermal Mass" on Page 76), or by insulating their
cold frames' sides with mounded-up soil, straw bales, or bags of leaf mulch.
In the fall of 2013, the experimental
cold frames were planted with hardy, cold weather crops such as lettuce, radishes, beets, pansies, and sage.
By contrast, a
cold frame tends to be more permanent - a base of bricks or railway sleepers to the height of about 20in and covered by toughened glass, often at a slight angle to stop the rain collecting on top.
Cold frames are permanent structures used to lengthen the growing season and are an excellent way to grow winter crops.
Vegetables that thrive in cool weather--such as greens and root vegetables--do best in
cold frames. On the other hand, sprawling summer favorites like cucumbers, tomatoes and squash will find the box too confining.
Below that is a
cold frame made with straw bales topped with salvaged windows.
EXTEND your season with a
cold frame. You can buy all-glass frames, which are great for spring crops, or buy or build a simple wooden box with glass window sash as a lid.
Greenhouse growers have long used
cold frames to harden off vegetable and flower seedlings.
There were many smiling faces on the plot last week but plenty of work to do now the ground has softened up and is ready to accept all the plants that have been chomping at the bit to leave the
cold frames. Seed sowing has also gathered momentum, hastened on by the perfect ground conditions.
Cold frames and hoop houses are a great way to take your seed-starting projects outdoors.
The answer is to build a simple
cold frame, essentially a bottomless, four-sided box with a glass, plastic or similar transparent cover that allows sunlight to penetrate.
Continue to sow carnations, pinks and other dianthus varieties in
cold frames or an unheated greenhouse.
Keep an eye on plants in
cold frames, watching out for slugs and rotting leaves.
Continue to feed with an ericaceous liquid feed in summer and keep under
cold frames over winter.
