Назначение теплиц

2. Purpose of greenhouses

Our northern nature is so harsh, and the summer is so short, that some garden plants (vegetables), mainly plants of the south, do not have time to ripen under normal conditions of sowing in the ground. If they do, it's too late.

Therefore, in the north, some vegetables have to be grown first in seedlings and, only with the onset of warm weather, they are planted in the ground already quite strong and strengthened.
The most practical and most common method for early forcing vegetables is the method of growing seedlings in greenhouses and nurseries. However, a greenhouse in a peasant economy is still considered an unattainable luxury, and meanwhile it should really take pride of place in every economy, especially in the suburbs, since it makes it possible to get vegetables for your table much earlier than ordinary difficult ones and, moreover, can be very profitable.
When arranging greenhouses, you need to keep in mind that they give a high, without sharp fluctuations, temperature for the plants grown in them. To do this, greenhouses are warmed with such materials that give a lot of heat when they rot; this includes: manure, tree leaf, bark, etc.
Greenhouses according to their structure, the content of warming materials and the time of their use are divided into: warm-early, semi-warm-medium and cold-late.
a) Warm or early. The earlier greenhouses are warmed up - for example, in the middle of January and in February - the more they should contain warming material, because the ambient temperature at this time of the year is very low, and there are too few sunny days. In view of this, one has to rely exclusively on the heat developed by manure or other warming substances.
b) Semi-warm or medium. These greenhouses are arranged a little later than the first ones and may contain less warming materials, since then the sun already warms the air and the ground well in the greenhouse. This type of greenhouse is perhaps the most common for all kinds of crops: for sowing cabbage seedlings, forcing cucumbers, radishes, lettuce , etc., plants. These greenhouses are stuffed in our north: for forcing cucumbers, radishes and lettuce at the beginning of March, and for sowing cabbage seedlings from the 20th of March until the end of this month.
c) Cold or late. For the very late forcing, for example, April, greenhouses are arranged completely without warming substances or they put the smallest amount of them (a layer of 4–5 inches). In April, the ambient temperature is higher and less heating materials are needed; sometimes even the warmth of the sun's rays, which the greenhouse earth absorbs during the day, is enough for plants.
d) An above-ground greenhouse should be arranged only in cases where underground water is close, which, penetrating into the greenhouse, cools it, or in the case when the greenhouse, due to necessity, has to be built in a hollow. In central Russia, one has to meet above-ground greenhouses more often, since there one does not have to deal with such cold weather as we encounter in the north.
The elevated greenhouse consists of one log cabin without a pit. The height of the back wall of the log house is 1 1/4–1 1/2 arshins, and the front wall is 1 arshin; for later distillations, the walls are made somewhat lower. A log house for such greenhouses is certainly built on moss or tow, although the laying for both of them needs to be made thin. The lower rows of the log house are tarred with resin and laid with manure. Stuffing the greenhouse with manure and filling the earth are done in the usual way.
d) Nurseries. Where spring comes earlier than near Petrograd, and stands relatively without sharp fluctuations in temperature, it is possible to use nurseries instead of hotbeds for growing cabbage seedlings. Near Petrograd, seedlings sown in greenhouses can be dived into these nurseries.
For a nursery, the same box is made as for a cold greenhouse, even from thinner boards. And if there are no rats or mice in a given place, and most importantly, spring or groundwater does not stagnate, then you can completely place a nursery on the ground. Otherwise, it has to be placed on legs, with a height of 8–10 inches. A platform of boards is attached to the legs and a box is already placed on it. The height of the back wall of this box is 8–10 vershoks, the front 6–8, and the side walls are beveled accordingly. The front wall should face south and the back wall north.
These nurseries are used, of course, after severe frosts have passed, since they are not covered with frames, but only with mats or mats, and then only at night. Sometimes cabbage, rutabaga, etc. are sown directly in them. plants, and sometimes (as, for example, in the Petrograd province.) They only dive seedlings from hotbeds. Before using them, at the bottom of the nursery, although not always, they put a layer of hot horse manure in 4-5 and then immediately put thawed (thawed) greenhouse soil on the manure, and then use them as cold greenhouses.
Drawing up a master plan for greenhouses
The initial data for drawing up the master plan are the characteristics of the construction site, the availability of engineering communications and transport links.
Basic requirements for sites allocated for the construction of greenhouse complexes.
The selection of a site for the construction of large greenhouse complexes is part of the work performed at the pre-design stage. The site is selected by the commission, which should include representatives of the customer and the design organization. The choice of a site is made out by the act.
In connection with the significant costs for the construction of residential and cultural buildings, sometimes reaching 40 % of the costs according to the total estimate, when choosing sites, one should first of all take into account the presence of a reserve labor force in the construction area. Preference is given to areas remote from the city, located in close proximity to district centers, urban-type settlements and normative rural settlements. It is desirable to have a reserve area for the expansion of the complex.