The smog in northwest China is serious. How to increase light for greenhouse vegetables in winter?

In winter, the temperature is greatly reduced, the illumination time is shortened, and the weather is foggy, indicating that vegetable greenhouse growers are busy. Many farmers have encountered such a situation. Insufficient illumination in vegetable greenhouses has led to a serious reduction in vegetable production. What should I do if the light in vegetable greenhouse is insufficient in winter? Let's have a look.

Why should winter vegetables be full of light?

What vegetable greenhouses need most in winter is sunshine. If the sunshine is insufficient, it needs to be supplemented. In the process of planting vegetables in greenhouse in winter, if no supplementary light measures are taken, not only the vegetable yield will not be improved, but also the quality of vegetables will be affected, and the growth cycle of vegetables will be prolonged, which will eventually lose the significance of planting vegetables in greenhouse in winter.

Method for supplementing light in vegetable greenhouse in winter

1. Planting vegetables in winter requires that the shed surface has a large angle (about 25) and is arched to facilitate lighting. Shed width and back slope width: for winter production, the shed width is 6 ~ 6.5m, and the horizontal distance of back slope is 0.8~ 1 m, which is convenient for lighting and heat preservation;

2. Using scientific and reasonable planting methods, when planting different kinds of vegetables in the greenhouse, we should follow the principle of high in the north and low in the south, so as to avoid letting high crops block low crops and make the plants receive light evenly.

3. If cucumber, kidney bean and other greenhouse vegetables are cultivated in winter, waste film can be used to replace the greenhouse as a clothes hanger, which can effectively improve the utilization rate of light energy.

4. Spray Yifuyuan planting bacteria liquid regularly. Photosynthetic bacteria in em bacteria can promote photosynthesis and stimulate crop growth.

5. The quality of greenhouse film directly affects the transmission of sunlight and the quality of light, so we should choose a greenhouse film with strong light transmittance and good quality. 0. 10-0. 12mm PVC long-life non-dripping film is the most widely used in production, with good light transmittance and heat preservation performance.

6. Insist on cleaning the dust and sundries on the greenhouse film, which can increase the light by more than 30%. In addition, it is necessary to clear the snow on the shed film in time after it snows, so as to increase transparency and light input.

7. Using mechanical roller blinds to open the curtains in time can not only shorten the opening time of grass curtains (or insulation quilts) and effectively extend the illumination time of greenhouse vegetables, but also extend the illumination time of greenhouse by opening the curtains in advance and delaying the opening.

Generally, the curtain rises from 0.5 hours to 1 hour after the sun comes out. It's best to cover the curtain half an hour before sunset, not too late.

8. The vegetable field in the greenhouse can be covered with plastic film, and the reflected light formed after the plastic film is covered can also enhance the light intensity of the vegetable base, make up for the shortage of direct light at the base, make the fruits and vegetables well colored, and prevent the lower leaves from premature aging.

9. Hang a reflective curtain. Hanging reflective curtain on the north side of greenhouse or near the back wall can obviously enhance the light intensity of vegetables near the back wall and improve the vegetable yield in this area.

10. Artificial fill light. Using incandescent lamp, iodine lamp, fluorescent lamp and high-pressure gas discharge lamp for artificial light supplement in vegetable greenhouse can make up for the lack of light in vegetable greenhouse under certain conditions of continuous cloudy and weak light environment, effectively maintain the normal growth and development of greenhouse crops and improve the yield and quality of crops. 1

1 1. Timely pruning and raking vegetable plants and knocking out old leaves, diseased leaves and dead leaves also have obvious effects on improving light conditions and increasing vegetable yield in greenhouses.