greenhouse

right|thumb|Victoria amazonica (giant Amazon waterlilies) in a large greenhouse at the [[Saint Petersburg Botanical Garden]] A greenhouse is a structure that is designed to regulate the temperature and humidity of the environment inside. There are different types of greenhouses, but they all have large areas covered with transparent materials that let sunlight pass and block it as heat. The most common materials used in modern greenhouses for walls and roofs are rigid plastic made of polycarbonate, plastic film made of polyethylene, or glass panes. When the inside of a greenhouse is exposed to sunlight, the temperature increases, providing a sheltered environment for plants to grow even in cold weather.

The terms greenhouse, glasshouse, and hothouse are often used interchangeably to refer to buildings used for cultivating plants. The specific term used depends on the material and heating system used in the building. Nowadays, greenhouses are more commonly constructed with a variety of materials, such as wood and polyethylene plastic. A glasshouse, on the other hand, is a traditional type of greenhouse made only of glass panes that allow light to enter. The term hothouse indicates that the greenhouse is artificially heated. However, both heated and unheated structures can generally be classified as greenhouses. thumb|Young tomato plants for transplanting in an industrial-sized greenhouse in the Westland (region), Netherlands|Westland, Netherlands