The most basic definition is "an enclosed structure used to facilitate the cultivation of plants that require regulated climatic conditions." Most often, these growing spaces have clear glass or plastic panels for the ceiling and walls, allowing light and warmth from the sun to shine into the structure's interior. The original intent of a greenhouse was most likely to protect growing plants from freezing temperatures during the winter, but the focus has been vastly expanded. Today's greenhouse may be small and extremely simple, or can become industrial-size structures that extend over large tracts of land.
Most plants are green; therefore the early structures used to facilitate plant growth were named "green houses." The varieties of vegetables, fruits, herbs, spices, flowers and medicinal plants that can be grown in modern greenhouses is virtually unlimited, and the development of new agricultural techniques and technology has made it possible to grow non-native species throughout the world. High-tech commercial greenhouses are virtual "laboratories" with computer-controlled equipment to monitor conditions such as heat and humidity, cooling, lighting and growth. Greenhouse growing is a broad field of study and experimentation in today's world, and the future growth of greenhouse agriculture is assured by new discoveries and development of more effective planting, growing and harvesting techniques.
