How to prevent spring frost (late frost)?

Spring frost (late frost) refers to the phenomenon that the temperature drops below 0℃ after the spring temperature warms up. When the average temperature of the day drops to the minimum (critical temperature) of the growth and development of pear trees, some organs of pear trees will be frozen.

The main organs of pear trees damaged by spring frost are buds, flowers and young fruits. Some foreign scholars believe that the dangerous temperature of freezing injury in bud stage is -2.2℃, and the flowering stage is-65438 0.7℃. Some people think that -3 ~- 1℃ flower organs will be frostbitten to varying degrees. But it depends on the duration of low temperature. Generally, the duration of low temperature is less than 4 hours. Although there is freezing injury on the surface of plant organs, it can usually be recovered.

Main measures to prevent frost in spring:

First of all, choose the late frost resistant varieties suitable for cultivation in this area.

The second is to delay the flowering period, so that the flowering period is after the late frost. Such as pear orchard irrigation or sprinkler irrigation, B9 spraying before flowering, trunk coloring, etc.

The third is the smoking method. According to the weather forecast, a number of smoke piles will be set up in the orchard the night before the frost. When the temperature in the canopy drops to 65438 0℃, smoke will be released, which will cover the pear orchard, reduce the ground heat dissipation and warm the air in the orchard.

Fourth, the remedial measures after frost are: strengthening the management of soil, fertilizer and water to promote growth; Spraying boron, urea and gibberellin. Putting it on a flowerpot can improve the fruit setting rate.