How to improve the light intake of vegetable greenhouses? A detailed guide to practical measures

The light conditions inside a greenhouse directly affect the growth and development, yield and quality of vegetables. This is especially true during rainy, snowy and icy weather, when light is weak. Insufficient light in greenhouse vegetables is a widespread problem. When light is insufficient, not only can vigorous photosynthesis not take place, but transpiration is also reduced, plants grow spindly and weak, and the yield and quality of vegetables suffer. Therefore, adopting some effective measures to improve the light conditions inside the greenhouse is very necessary for greenhouse vegetable production. The measures are:

Reasonable layout. When growing different kinds of vegetables in a greenhouse, follow the principle of "tall in the north, short in the south" so that plant heights are arranged in orderly, staggered fashion and mutual shading is minimized. When transplanting a single kind of vegetable, aim for seedlings of uniform size so that plants grow evenly and shading between plants is reduced. At the same time, it is best to make beds and plant in a north-south orientation so that the plants receive as much sunlight as possible.

Keep the greenhouse film clean. Water droplets, dust and other debris on the greenhouse film can reduce light transmittance by about 30%. After new film has been in use for 2 days, 10 days and 15 days, the light inside the greenhouse weakens by 14%, 25% and 28% respectively. Therefore, frequently sweep and rinse away dust, dirt and water droplets on the film surface, and keep the film surface clean, in order to increase the transparency of the greenhouse film.

Reasonable uncovering and covering of straw curtains. On the premise of doing a good job of insulation, uncovering the insulating straw curtains somewhat earlier and covering them somewhat later can extend the lighting time and increase the amount of light collected. Generally, uncover the curtains 0.5-1 hour after the sun comes up, and cover them again half an hour before the sun sets. Especially on rainy days when the rain stops and starts, the curtains should also be appropriately uncovered to make full use of the sun's scattered light.

Choose drip-free film. In the production formula of drip-free film, several surfactants are added, which greatly weakens the affinity between water molecules and the film, so water droplets flow along the film surface to the ground without forming droplets. Using drip-free film to cover the greenhouse can increase the light intensity inside the greenhouse and raise the greenhouse temperature.

Set up reflective screens. Using aluminized reflective screens 2 m wide and 3 m long, hung on the north side inside the greenhouse so that they are perpendicular to the ground, can increase ground light by about 40% and raise the greenhouse temperature by 3°C-4°C. In addition, laying silver-gray plastic film on the ground can also increase the light intensity between plants.

Do a good job of plant training. Timely field management such as pruning, removing side shoots, tying vines and removing old leaves helps improve ventilation and light penetration inside the greenhouse.

Sunlight is a necessary condition for green plants to carry out photosynthesis. In seasons with few sunshine hours and low intensity, collecting more sunlight in the greenhouse plays an important role in improving vegetable yield and quality.