This post is created to make people aware of how profitable it can be to have a greenhouse at home.
Have you ever wondered, if the flowers bloom in spring and the tomatoes ripen under the heat of summer, how is it possible that they can be bought all year round? Well, this is possible thanks to the greenhouses.
The greenhouses allow you to obtain fruits and vegetables at any time of the year. Nevertheless, how is it possible for vegetables to grow regardless of the season of the year?
A greenhouse is used for crop production, usually equipped with a translucent glass or plastic exterior covering, which allows the control of temperature, humidity and other environmental factors to favor the development of the plants.
In a greenhouse the effect produced by solar radiation is used, which, when passing through a glass or translucent material, heats the objects that are inside.
In a greenhouse you can control how much heat enters and how much heat is released, so that the environment inside is optimal for what is being produced, this makes it even possible to grow in cold countries like Afghanistan in the middle of winter, including the plants that they are only from predominantly warm places.
Take advantage of the effect produced by the solar radiation produced by the sun that, when passing through a glass or other translucent material, heats the objects inside; these, in turn, emit infrared radiation, with a wavelength greater than the solar, so they cannot pass through the glass when they return, being trapped and producing heating.
The sun’s emissions towards the earth are in short wave while from the earth to the outside they are in long wave.
The principles of the Greenhouses
The greenhouses facilitate some fundamental principles. The diffusion of the light, that causes that all the plants to the interior obtain the sufficient one, have a harmonic development, and produce homogenous and salubres fruits; photosynthesis is enhanced thanks to the homogeneity in temperature and light, and also allows you to program crops for times of scarcity thanks to its micro climate property.
Besides the glass or plastic used for a greenhouse works as a selective medium of transmission for different spectral frequencies and its effect is to trap energy inside the greenhouse, which heats the interior environment. It also serves to prevent the loss of heat by convection. This can be demonstrated by opening a small window near the roof of a greenhouse: the temperature drops considerably. This principle is the basis of the automatic self-cooling system.
In the absence of a coating, the heat absorbed would be eliminated by convective currents and by the emission of infrared radiation (wavelength greater than visible).
The presence of crystals or plastics prevents the transport of accumulated heat to the outside by convection and obstructs the output of a part of the infrared radiation. The net effect is the accumulation of heat and the increase in the temperature of the enclosure.
Types of Greenhouses
There are two main classes of greenhouses:
- The traditional, “classic” or home greenhouse consists of a kind of house with glass roof and walls. They are usually small greenhouses and are usually heated and equipped with devices through which the required degree of humidity is produced.
However, if the place where the greenhouse is located is not very cold, it is sometimes possible to dispense even with heating.
The small greenhouse serves fans to grow flowers and ornamental plants, but for small orchards. You can also hear it as a hydroponic greenhouse
- The industrial greenhouses, which lately have had a great development. In most cases, they are large and have walls and a transparent plastic roof. In these greenhouses, flowers and vegetables destined for commerce are planted.
Producing any vegetable or fruit in a greenhouse obviously costs more than in the open. However, the gains are greater, since the consumer to be able to achieve these fruits out of season is willing, usually, to pay something more expensive.
Eating for example fresh tomatoes in the middle of winter is certainly pleasant. But these same tomatoes, which as we have seen cost a lot, are less tasty , less aromatic and less rich in vitamins than those that ripen under the summer sun.
The benefits of Greenhouses
- They are a great ally in cold weather to continue generating crops.
- The homemade greenhouses provide protection against the cold and, therefore, it is possible to sow the seeds in advance.
- Being a closed environment, crops are isolated from pests and diseases and, if they occur, it is easier to control them.
- The covers promote a better propagation of light, which in turn facilitates photosynthesis.
- You can do experiments and cultivate for example species that would not occur outdoors, like tropical plants that need more heat.
Boustan Sabz Agriculture Company has 40 established greenhouses each covering 400 square meter area, which grow a wide range of agricultural products. More greenhouses are planned in the future for extensive production as well as for research and development purposes; part of which will be the two Mega greenhouses making a history in agriculture sector as the first biggest greenhouses in Afghanistan each covering (10,080 square meter) area.