Greenhouses are prefect for someone wishing to grow plants year around. But how do they work? Greenhouses are usually made of glass or plastic. Why? Because greenhouses use solar radiation to trap heat inside and the glass/plastic allows heat to enter easily into the building structure. This design helps create an artificial environment to sustain plants inside when it is too cold outside. The heat from the sun enters through the roof and warms the plants and soil inside. As the heat around the soil begins to rise it is replaced by surrounding cool air which immediately starts to warm up. This system rapidly warms the greenhouse.
In temperate climates (growing season and a dormant season in which temperatures can get below zero) additional heat sources may be needed, including heat fans. As plants absorb the energy of the sun, they do not emit it quickly but instead retain it, which is another reason why the greenhouse stays so warm. There is a chance of overheating occurring, which is why vents need to be installed near the roof to let lighter/hotter air escape and near the floor where cool air can enter. Greenhouse plants also need plenty of water. To make it easier, drip irrigation systems are commonly used, along with overhead sprinklers.
Greenhouse sizes vary. The larger the greenhouse, the more expensive it will be. Greenhouses can be purchased or built. Building a greenhouse used to be difficult but now there are materials you can buy that are specifically designed for building a greenhouse. Keep in mind that greenhouses are also beneficial to the environment because they reduce fossil fuel use by allowing us to grow local vegetables and fruits during cold months rather than having to import them. If you would like to improve the environment and have plants and vegetables available to you year round, consider investing in a greenhouse!
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