How to water vegetables in greenhouses in winter? These watering principles you need to master
After the start of winter, the temperature gets lower day by day. Many vegetable growers find that after watering, the leaves of the vegetables gradually turn yellow, and some vegetables even stop growing or even die. So how should vegetables in greenhouses be watered in winter? Let's take a look at the detailed introduction.
1. Water on sunny days, not on cloudy days
This means watering on sunny days and not watering on cloudy days. The specific watering time should be chosen according to climate changes, and the principles of watering on sunny days, watering less or not at all on cloudy days, and avoiding watering on rainy and snowy days must be strictly followed. Especially during cold waves and cloudy, snowy days, watering should be avoided as much as possible during this period, so as to prevent the ground temperature from dropping and causing root rot and dead plants, or causing the air humidity in the greenhouse to increase, leading to the occurrence and spread of diseases.
2. Water little, not much
In winter, the temperature is relatively low, and the water demand of vegetables is also relatively small, so the number of waterings should be small and the amount of water should also be small. Flood irrigation should not be used. Under normal circumstances, small amounts of water are applied to alternate rows, and the watering amount is at most only about the usual amount in summer. This can reduce the impact of watering on low temperatures and ensure the growth and development of crop roots.
3. Water with warm water, not cold water
Winter temperatures are low. If cold water is used for irrigation, it will cause the ground temperature to drop, which is extremely unfavorable to crop growth. Therefore, irrigation water should first be preheated in the greenhouse, and irrigation should be carried out when the water temperature is close to the ground temperature. The water temperature should preferably not be lower than 12 degrees. In addition, cold water from rivers, reservoirs and ponds must not be used directly for irrigation. After watering, the ventilation openings can be properly closed so that the temperature rises above 30 degrees and stays there for 1-3 hours.
4. Water under cover, not in the open
For greenhouse vegetables in winter, we must persist in doing under-film drip irrigation or under-film micro-irrigation. Only in this way can we effectively prevent ground moisture from evaporating, reduce the air humidity in the greenhouse, and prevent the occurrence of diseases. Moreover, the use of under-film micro-irrigation can coordinate the water, fertilizer, air and heat needed for vegetable growth. Especially when used in the early and middle stages, micro-irrigation is beneficial for promoting root growth and controlling seedlings, controlling the air humidity in the greenhouse, and reducing the occurrence of pests and diseases. At the same time, it can also effectively control the amount of water, reduce fertilizer loss, improve soil structure, promote crop growth and development, and improve vegetable quality.
The above is an introduction to the watering principles for greenhouse vegetables in winter. I hope it can help you. If you want to learn more related knowledge, please follow us.