How Does A Greenhouse Work?
The purpose of greenhouses is to allow gardeners to grow a wider variety of plants and flowers, no matter the growing zone, and to extend the growing season to three, and sometimes four, seasons. No matter what size the greenhouse, the interior of a greenhouse heats up because the sunlight shining through greenhouse windows warms everything inside faster than heat can escape. The greenhouse walls and roof keep the warm air inside, even when temperatures outside are chilly. Greenhouse kits are the most common method of installing a home greenhouse. They come partially pre-assembled and can be put together in a very short amount of time.
greenhouse work on the principal that heat can enter thru the glass from the sun, and then becomes trapped inside because it cannot escape very effectively thru glass. in more northerly climates, there are shorter days so extra lighting may be neccessary. keep in mind, however that some plants need shorter day lengths to come into bloom–chrysanthemums and poinsettias for example. extra heating will also be neccessary in very cold climates, even tho a well-built greenhouse can be many degrees warmer than outside on a winter day even without additional heating. commercial greenhouses are quite expensive to maintain and operate and need to be doing well financially to make a good profit. if its just one that you’ve tacked on to your house for your personal enjoyment, then cost will be low (depends on the quality of glass used, and if its insulated, etc. I have a home-made greenhouse thats attached to the south wall of my porch.
You almost have it right. It is just your basic understanding of the principles involved. The glass admits sunlight from the exterior in. Plants absorb some. remember, the purpose of the greenhouse is to grow plants in a warm environment. After being directly admitted, the light gets scattered inside, off leaves, off walls, off the glass and particularly off and by water vapour which will develop within the green house. This in particular is like having a blanket over the interior top of the greenhouse, preventing interior warmth from directly escaping while the rest of the world outside may cool down. During winter, rain clouds can keep the region below much warmer by blocking much of the direct radiation of accumulated heat in the earth from escaping into outer space during the night. It is not all blocked, but much is retained. Next day during sunlight, that lost energy gets replenished.
Britannica Concise Encyclopedia: greenhouse Building designed for the protection of tender or out-of-season plants against excessive cold or heat. Usually a glass- or plastic-enclosed structure with a framing of aluminum, galvanized steel, or such woods as redwood, cedar, or cypress, it is used for the production of fruits, vegetables, flowers, and any other plants requiring special temperature conditions. It is heated partly by the sun and partly by artificial means. This controlled environment can be adapted to the needs of particular plants. Columbia Encyclopedia: greenhouse enclosed glass house used for growing plants in regulated temperatures, humidity, and ventilation. A greenhouse can range from a small room carrying a few plants over the winter, to an immense heated glass building called a hothouse or conservatory, covering acres of ground and used for forcing fruits or flowers out of season. Greenhouses have long been used for holding plants over cold seasons and for growing t
