How to prevent and control low-temperature freezing injury in napa cabbage? A full analysis of the latest measures

After Frost's Descent, temperatures drop sharply. For early-planted autumn cabbage, the continuous harvest period has now arrived, while for late-planted cabbage, work to prevent low-temperature freezing injury must be done well at this time, otherwise it is highly likely to cause large-scale yield reduction.

I. Low-temperature damage

Low temperature harms cabbage in two ways. The first is low-temperature damage, also called chilling injury, which mainly occurs during the heading stage of cabbage. When the temperature is below 10°C, the growth rate of napa cabbage becomes extremely slow, and when it is below 5°C, growth basically stops. In the north, temperatures drop faster than in the south, and cold waves also arrive earlier, causing temperatures to fall sharply and leading to loose heads, lower yield and poorer quality. The second is freezing injury. When cabbage is grown in northern regions, about half a month before harvest, sudden cold waves and snowy weather may occur, with temperatures dropping below 0°C, which can very easily cause freezing injury to cabbage leaves that is difficult to recover from.

II. Prevention and control measures

1. Watering

After a strong cold air mass invades, if the weather is clear, there is no wind or only a slight breeze at night, and the temperature drops rapidly, especially when the surface temperature falls below 0°C, a large amount of well water can be irrigated at this time to raise the ground temperature, bringing the surface temperature up to about 8°C, thus avoiding frost damage. Generally, irrigation is done in North China in early to mid-November, in Northeast and Northwest China in mid to late October, and in the Yangtze River basin from late November to early to mid-December.

2. Spraying water

Before frost occurs, a sprayer can be used to spray water on the plant surface. This can slow the drop in plant temperature and also increase the water vapor content in the air, causing water vapor to condense and release heat, thereby moderating the frost.

2. Spraying cold-resistance agents

You can use 100~300 milliliters per mu of a plant cold-resistance agent or stress-resistance yield-increasing agent, dilute it with water, and spray it on the plants, which can also produce a very good cold-resistance effect.

  The above is an introduction to prevention and control measures for low-temperature freezing injury in napa cabbage. We hope it can help you. To learn more related knowledge, please keep following us.