How to remedy greenhouse vegetables after freezing? These methods must be mastered

1. Manual water spraying. Once greenhouse vegetables are frozen, a sprayer can be used inside the greenhouse to spray water onto the vegetables. This can increase the air humidity inside the greenhouse, stabilize the temperature inside the greenhouse, and inhibit water evaporation from the frozen tissues of the vegetables, prompting the frozen tissues to absorb water and recover their vitality.

2. Ventilation to lower temperature. After greenhouse vegetables suffer freeze damage, the greenhouse must not be closed immediately to raise the temperature, because if the temperature rises too quickly the frozen tissues will dehydrate and die. The correct method is to ventilate to lower the temperature so that the temperature inside the greenhouse rises slowly, giving the frozen tissues sufficient time to absorb the water lost due to freezing, thereby promoting cell revival and reducing tissue necrosis.

3. Prune away dead branches. Promptly prune away the frozen stems and leaves to prevent the frozen tissues from becoming moldy and diseased and inducing disease.

4. Set up shading in the greenhouse. Build shading inside the greenhouse to prevent the frozen vegetables from being exposed to direct sunlight and slow down the water loss of the frozen tissues.

5. Fertilizer supplement. After the frozen plants recover from transplanting shock, promptly apply an appropriate amount of quick-acting fertilizer. This can improve the nutritional status of the vegetables and enhance the plants' cold resistance and freeze resistance. Foliar spraying saves fertilizer and takes effect faster than soil topdressing, and should be sprayed reasonably according to the fertilizer requirements of different crops.

6. Apply pesticides to prevent disease. After plants are frozen, diseases easily take advantage of the weakness, so protective agents and disease-and-pest control chemicals should be sprayed promptly, such as 80% mancozeb 500-fold solution, 64% carbendazim and thiram, etc. At the same time, place fumigants inside the greenhouse to kill pathogens in the greenhouse.

Chengde County Agriculture and Animal Husbandry Bureau Sun Lili Ren Meihong