Cold frame extends the gardening season
Plants cultivated under foil or glass benefit from warm and moist air. The prevailing climate in a cold frame ensures faster and more even growth, which has a particularly beneficial effect on plant reproduction and the cultivation of young plants. In addition, in the protected atmosphere of a cold frame, fresh vegetables can be grown and harvested much earlier in spring and a few weeks longer in autumn - if you combine the advantages of a raised frame with those of a cold frame, you can start growing Start lettuce and other early vegetables. When the last night frosts are over at the end of May, you can remove the attachment and the cold frame becomes a normal raised bed again.
also read
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How to convert your raised bed into a cold frame
There are several ways to convert the raised bed into a cold frame. Covers, for example made of glass or acrylic, should always be installed at a slight angle, facing south. In this way, the rays of the sun, which is still low on the horizon in the evening and morning, reach the little plants in the bed. You should also make sure that the cover of the attachment closes well with the raised bed edge - the more effectively the heat is stored inside the cold frame.
Cold frame attachment made of glass or acrylic
A cold frame attachment for the raised bed can be bought ready-made or you can easily build it yourself. All you need is a few slats, which you saw to size to fit the bed box and put together. The lid also consists of a slatted frame in which glass or acrylic panes (alternatively, transparent film can also work) is attached. The rear part of the cold frame is always significantly higher than the front, after all, the last ray of sunshine should be captured. The lid also needs anchoring so that it can be set up for ventilation. A cold frame attachment made of aluminum and double sheets made of plastic are particularly light.
Polytunnels
A foil tunnel (€ 7.94 at Amazon *) is probably the simplest variant of a cold frame. To do this, insert several bent metal rods into the soil of the raised bed at a distance of approx. 40 centimeters so that they span the narrow side. In a wooden raised bed, you can attach eyelets to the inside on the sides and insert the metal rods into them. Pull a film over the rods and attach it to the side, e.g. B. with stones. To ventilate and harvest, simply slide the film up on the sides.
Rotting manure warms the plants from below
In autumn or late winter, pour horse, cattle or small animal manure about 10 to 20 centimeters high into the raised bed and fill it with a layer of planting substrate that is about 15 centimeters thick, so the rotting manure acts as underfloor heating for the plants that need warmth. If you don't have manure on hand, you can also use pellets made from cattle manure (€ 17.80 at Amazon *), which can be bought in handy buckets. But also straw with husks, well soaked in nettle manure, can replace the animal dung.
Tips
If the raised bed is provided with a foil tunnel or a glass or acrylic cover, you only need to water a little. Under such a cover, the substrate develops permanent moisture that makes constant watering unnecessary. However, ventilate regularly and often to prevent mold from settling in this humid microclimate.
