Of course, in order to harvest in the greenhouse early, you will have to take care of heating without fail, since even impermeable polycarbonate walls do not provide the temperature necessary for ripening in the conditions of our winter. The cheapest, almost free, even option to get heating for the greenhouse is if you are so lucky that it is under your site that a section of the heating main passes. Then, having found this place, erect a greenhouse on it, and the heating problem will be solved for nothing.
Do-it-yourself solar panels in a greenhouse
But such a successful passage of the heating main is, of course, the exception rather, therefore, we turn to other inexpensive methods of heating the greenhouse. The sun gives us free energy, we just need to save it and use it at the right time. On a sunny day, the temperature in the greenhouse can reach + 40 °, but with the onset of twilight it sharply decreases. To save heat, you can arrange a homemade solar battery in the greenhouse. To do this, dig a hole of approx. 15 cm and line it with polystyrene or other material with good thermal insulation properties. Lay a polyethylene film on top for waterproofing. Pour coarse-grained moistened sand onto polyethylene, and then fill the pit with earth. This rather primitive design will accumulate heat during the day and gradually release it at night, heating the air in the greenhouse. But due to the lack of sunny days, this method is unlikely to become the main one, so it is better to use it as an additional one along with other heating methods.
Heating the greenhouse with manure is quite effective, which is relatively cheap, as well as safe, environmentally friendly and beneficial for plants receiving mineral recharge along with the heat. Heat is generated due to the chemical processes of decay. Manure of different origin releases heat in different quantities. The highest temperature up to 33-38 ° can provide horse manure, and for up to 90 days. The heat generated by cow waste maintains the temperature for 12 days at a level of 12-20 °, pig manure is less effective, but it is also able to keep the temperature in the range of 14-16 ° to 70 days. By the way, the heat generated by plant waste is also very significant, for example, rotted bark heats the soil for almost 4 months to 20-25 °, and sawdust heats the earth to 20 °, although only for a couple of weeks.
When it is required to warm the greenhouse in a short time, you can use winter wheat straw or rotten foliage, the temperature will quickly increase by 40-45 °, but the effect will be short-lived, then you need to continue heating by other methods. Experienced gardeners using the biological method of heating the greenhouse combine several types of fuel: manure with sawdust and bark, straw with manure, sawdust with bark. To whip up heat-generating processes, hot water or quicklime is poured into the waste. An important condition for the success of heating in this way is the presence of nitrogen fertilizers in the ground, good aeration and a normal level of humidity in the greenhouse.
Another inexpensive way of heating can be used for a film greenhouse, which can be arranged with one's own hand - air heating. To do this, you need a pipe of approx. 2-2.5 meters, quite wide - with a diameter of 50-60 cm. One end of the pipe is placed in a greenhouse, a fire is being lit near the other. Hot air will flow through the pipe directly into the greenhouse. This method has serious disadvantages - you have to constantly monitor the fire, and there is a certain fire hazard.
A safer and less burdensome way of heating the greenhouse will be to lay out a brick stove in the vestibule of the greenhouse. A chimney will leave from it, which will pass under the beds (racks) and exit from the opposite side. The fuel used is solid (firewood, coal) or gas. This method of heating is more advantageous than electric, especially for small greenhouses. The furnace should be located no closer than 25-30 cm from the wall of the greenhouse, the distance from the garden (rack) to the top of the hog is not less than 15 cm.
In addition, there is water heating of greenhouses, which is one of the most effective ways.