Detailed Explanation of Key Points for Winter Frost Protection of Greenhouse Flowers

1. Add covers. At night, set up a small tunnel inside the greenhouse and add straw curtains. Adding straw mats or corn stalks around the greenhouse at night can raise the temperature by 1°C to 2°C. Adding a thin mat on top of the original straw mat can increase the greenhouse temperature by 2°C to 3°C. Covering the original straw mat with a layer of film can not only block the wind, but also prevent rain and snow from wetting the straw mat, thereby reducing heat loss caused by water evaporation. For flowers planted in the ground, plastic film mulching can also be applied, which can increase the soil temperature by more than 1°C after covering.

2. Smoke around the greenhouse. Before a cold wave arrives, light fires around the greenhouse to produce smoke, which can prevent heat around the greenhouse from radiating to the upper air and reduce heat loss.

3. Clean the greenhouse film. promptly remove dust, dirt and snow from the greenhouse film, which can increase light exposure and raise the greenhouse temperature.

4. Cover with plastic film or small arched tunnels. For high-ridge cultivation inside the greenhouse, a layer of plastic film can be covered on the high ridges, generally raising the soil temperature by 2°C to 3°C; for flat-bed cultivation, small arched tunnels can be set up to raise the soil temperature.

5. Dig cold-proof trenches. Dig trenches on the south side outside the greenhouse and fill them with insulation materials such as horse manure, weeds and straw, which can prevent soil heat from escaping outward and raise the soil temperature in the southern part of the greenhouse.

6. Double-film covering. Set up another layer of film below the anti-drip film. Because there is air between the two layers of film, the temperature inside the greenhouse can be significantly increased.

7. Water pool insulation. Dig a water storage pool every few meters in the center of the greenhouse, lay plastic film on the bottom of the pool, then fill it with clean water, and cover the upper part of the pool with a layer of transparent film (to prevent water evaporation in the pool from increasing the air humidity inside the greenhouse). Because water has a high specific heat, it can absorb heat at noon (when temperatures are high) and release heat at night.

8. Remove the straw mats at the right time. When temperature conditions permit, uncover as early as possible and cover as late as possible to promote photosynthesis in the flowers. In deep winter, on sunny days, generally remove the straw mats in the morning when sunlight falls across the entire greenhouse surface; at this time, the temperature inside the greenhouse is generally not lower than 18°C. On cloudy or overcast days, light is weaker, but the straw mats should still be removed at the right time to let scattered light enter. On one hand, this can raise the temperature; on the other hand, because scattered light contains more blue-violet light, it is beneficial to photosynthesis. Never leave the straw mats in place for a long time, causing the greenhouse to become cold and shaded and the temperature to drop sharply.

9. Apply more fertilizer. Apply heat-generating materials such as horse manure and chopped grass inside the greenhouse to raise the soil temperature. The decomposition of organic fertilizer can release heat. Applying an appropriate amount of organic fertilizer and phosphorus-potassium fertilizer can not only improve soil aggregate structure and raise soil temperature and provide nutrients for flowers, but also enhance the cold resistance of flowers.

10. Hang reflective curtains. Hang polyester aluminized film on the north side of the greenhouse, which can increase light inside the greenhouse and raise the greenhouse temperature by 2°C to 3°C.

11. Heating. In extremely cold weather, add a stove or turn on heating inside the greenhouse, but when using a stove fire for heating, pay attention to preventing gas poisoning of the flowers. A chimney should be installed to discharge the gas outside the greenhouse. Be careful not to burn firewood or grass inside the greenhouse to raise the temperature, because the smoke released when firewood and grass burn is extremely harmful to flowers.

12. Spread plant ash. Plant ash is gray-black and has a strong heat-absorbing capacity. After evenly spreading it on the greenhouse floor, it can generally raise the soil temperature by 1°C to 2°C.

13. Spray antifreeze. Before the temperature drops, spray the stems and leaves of the plants with a 400 to 700 times dilution of antifreeze, which can provide cold protection and frost resistance.