Evolved

The greenhouse has come a long way since it evolved.
Thousands if not millions of people world wide owe a living to the greenhouse, crops are grown in thousands of acres of glasshouses world wide and either sold on the home market or exported.
With the advent of D.I.Y. the glasshouse gardening market has grown year on year with thousands of keen enthusiastic gardeners growing their own tomato's, lettuces, bedding and pot plants just to name a few.
The UK 'Greenhouse' comes in different forms, mainly manufactured from Timber, (Wooden greenhouses are mostly built from Pine or Cedar), Aluminium (Either sold in 'Mill Finish' or 'Powder Coated' in a variety of colours), Steel hoops (covered with special polythene sheets) and now hard coloured Plastic.
A selection of greenhouse accessories have developed including Auto Vent Openers, Rainwater Kits, Shelving, Wooden and Aluminium Staging, Cresting and Finials, Louvre Vents, Partitions, Potting Benches and many more.

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Explanation

A greenhouse is structure with a glass or plastic roof and frequently glass or plastic walls; it heats up because incoming solar radiation from the sun warms plants, soil, and other things inside the building. Air warmed by the heat from hot interior surfaces is retained in the building by the roof and wall. These structures range in size from small sheds to a very large buildings.
The glass used for a greenhouse works as a selective transmission medium for different spectral frequencies, and its effect is to trap energy within the greenhouse, which heats both the plants and the ground inside it. This warms the air near the ground, and this air is prevented from rising and flowing away, in addition to the fact that infrared radiation cannot pass through the greenhouse glass. 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 [[autovent]] automatic cooling system.  Greenhouses thus work by trapping electromagnetic radiation and preventing convection.

Uses

The idea of growing plants in environmentally controlled areas has been around for a long time.  Doctors for the Roman emperor Tiberius  prescribed a cucumber a day for him. The Roman gardeners used artificial methods (similar to the greenhouse system) of growing to have it available for his table every day of the year. Cucumbers were planted in wheeled carts which were put in the sun daily, then taken inside to keep them warm at night. The cucumbers were stored under frames or in cucumber houses glazed with either oiled cloth known as "specularia" or with sheets of mica. (Pliny the Elder and Columella).

The first modern greenhouses were built in Italy in the Sixteenth Century to house the exotic plants that explorers were bringing back from the tropics.  They were originally called ''giardini botanici'' (botanical gardens).  The concept of greenhouses soon spread to Holland and then England, along with the plants.  Some of these early attempts required enormous work to close up at night, or to winterize.  There were serious problems with providing adequate and balanced heat in these early greenhouses.

Jules Charles, a French botanist, is often credited with building the first practical modern greenhouse in [[Leiden]], Holland to grow medicinal tropical plants.

Originally on the estates of the rich, with the growth of the science of botany greenhouses spread to the universities.  The British some times called their greenhouses ''conservatories'', since they conserved the plants.  The French called their first greenhouses ''orangeries'', since they were used to protect orange trees from freezing. As pineapples became popular ''pineries'' were built. Experimentation with the design of greenhouses continued during the Seventeenth Century in Europe as technology produced better glass and construction techniques improved.  The greenhouse at the [[Palace of Versailles]] was an example of their size and elaborateness; it was more than 500 feet long, 42 feet wide, and 45 feet high.

In the Eighteenth Century the largest greenhouses were built.  The conservatory at [[Kew Gardens ]]in England is a prime example of the Victorian greenhouse. Although intended for both horticultural and non-horticultural exhibition these included London's Crystal Palace, the Exhibition of the Industry of All Nations and Munich’s  Glaspalast.  Joseph Paxton, who had experimented with glass and iron in the creation of large greenhouses as the head gardener at Chatsworth, in Derbyshire, working for the Duke of Devonshire,  designed and built the first, London's Crystal Palace.

In Japan, the first greenhouse was built in 1880 by Samuel Cocking, a British merchant who exported herbs.

In the Twentieth Century the geodesic dome was added to the many types of greenhouses.

History

The idea of growing plants in environmentally controlled areas has been around for a long time.  Doctors for the Roman emperor Tiberius  prescribed a cucumber a day for him. The Roman gardeners used artificial methods (similar to the greenhouse system) of growing to have it available for his table every day of the year. Cucumbers were planted in wheeled carts which were put in the sun daily, then taken inside to keep them warm at night. The cucumbers were stored under frames or in cucumber houses glazed with either oiled cloth known as "specularia" or with sheets of mica. (Pliny the Elder and Columella).

The first modern greenhouses were built in Italy in the Sixteenth Century to house the exotic plants that explorers were bringing back from the tropics.  They were originally called ''giardini botanici'' (botanical gardens).  The concept of greenhouses soon spread to Holland and then England, along with the plants.  Some of these early attempts required enormous work to close up at night, or to winterize.  There were serious problems with providing adequate and balanced heat in these early greenhouses.

Jules Charles, a French botanist, is often credited with building the first practical modern greenhouse in Leiden, Holland to grow medicinal tropical plants.

Originally on the estates of the rich, with the growth of the science of [[botany]] greenhouses spread to the universities.  The British some times called their greenhouses ''conservatories'', since they conserved the plants.  The French called their first greenhouses ''orangeries'', since they were used to protect orange trees from freezing. As pineapples became popular ''pineries'' were built. Experimentation with the design of greenhouses continued during the Seventeenth Century in Europe as technology produced better glass and construction techniques improved.  The greenhouse at the Palace of Versailles was an example of their size and elaborateness; it was more than 500 feet long, 42 feet wide, and 45 feet high.

In the Eighteenth Century the largest greenhouses were built.  The conservatory at Kew Gardens in England is a prime example of the Victorian greenhouse. Although intended for both horticultural and non-horticultural exhibition these included London's |Crystal Palace, the Exhibition of the Industry of All Nations New York Crystal Palace and Munich’s  Glaspalast.  Joseph Paxton, who had experimented with glass and iron in the creation of large greenhouses as the head gardener at Chatsworth, in Derbyshire, working for the[Duke of Devonshire,  designed and built the first, London's Crystal Palace]].

In Japan, the first greenhouse was built in 1880 by Samuel Cocking, a British merchant who exported herbs.

In the Twentieth Century the geodesic dome was added to the many types of greenhouses.

Read the full story in Wikipedia