Different kinds of seedlings, in greenhouse cultivation process of water requirements are also different. The intensity of illumination in greenhouse is changed with the change of seasons and weather. In sunny days, indoor light is significantly higher than cloudy and cloudy. The vertical distribution of indoor illumination is influenced by indoor humidity, seedling type, height, density and leaf shape. In summer, the intensity of light, will burn seedlings, to pay attention to greenhouse canopy shade, shorten the intensity of light irradiation time. In winter and early spring, light intensity is small, management should try to make up for the lack of greenhouse light, as far as possible to extend daylight time, even rainy days should ensure that seedlings have a certain amount of light time, increased scattering light to promote the development of seedlings. In order to maintain proper air humidity and soil moisture, greenhouse engineering ensures the normal conduct of transpiration of seedlings and regulates water supply according to different nursery periods.
In order to meet the needs of greenhouse vegetables for illumination, it is necessary to install illumination control system to achieve a good light shed project. The intelligent greenhouse illumination system can balance the illumination balance after construction. When the sun is not enough, especially in winter need to fill the light system, crops between the necessary to install the light to fill light. Complementary light can increase crop growth and yield. The greenhouse shading system is also complementary to the construction of the light reinforcement system.