In terms of construction, warm and cold frames do not differ much from each other - warm frames usually have higher side walls, because their heating uses a natural source of heat - manure, which is an additional layer of substrate in the inspection. Sometimes permanent recessed frames are used, for which in the fall a pit with the dimensions of the frame and a depth of about 0.5 m should be dug.
In autumn, cover the pit with a layer of leaves or straw to avoid the ground freezing.In February or March, remove a part of this layer and place the frame in such a way that its edges are slightly recessed.
The removed layer should be replaced with a layer of manure, then a layer of leaves or straw chaff.The last layer is fertile, it can be compost mixed with peat or soil or universal soil.In the case of surface frames, the layering principle is the same, with the difference that a manure layer is not used for cold frames.
Each layer should be 20-30 cm high and compacted after application. However, in both cases, the soil under the frame must be dug and free of weeds. In a cold inspection, after digging the soil and applying a layer of fertile substrate (universal soil, ready-made soil for seedlings or mature compost mixed with peat and sand in the proportion 2: 1: 1), seeds can be sown starting from mid-March.In the warm inspection, the cultivation can start a month earlier, more or less in the middle of February.
When preparing a warm frame, after applying a layer of manure (or dry dust mixed with straw and warm water), allow it to heat up spontaneously, only then, after a few days, apply a layer of the substrate and leave it to heat again for a few days. In the initial period of cultivation, it is worth covering the frame with straw or fleece overnight, and during the day, especially in sunny weather, it should be aired.
