Orchard frost poses a serious threat to fruit trees
The orchard frost threatens the fruit trees the most, the light ones reduce
production, the heavy ones are out of production, and the disaster areas are
difficult to determine, the disaster period has changed, it is difficult to
control, and early prevention and disaster relief should be mitigated.
Immediately take effective measures after the disaster and strive to minimize
First, the type of frost.
1) Advance frost. The cold air mass below 0 °C flows in for 3~4d, the
temperature drops to -5~-3°C or even lower, and the fully active flowers, leaves
and tips are all seriously damaged. The general anti-frost measures are not
effective. The above large freeze damage is of this type.
2) Radiation frost. This type of frost is prone to occur when the average
daily temperature is low and the night is clear and windless. It is terminated
before sunrise and lasts for 0.5~10h. It may also appear in several nights,
usually down to -2~-1°C. Frost measures can be prevented.
3) Mix the frost. It began to invade by cold air masses, and then there was
radiation cooling at night, and the temperature dropped sharply. Such frosts
were difficult to prevent and fruit trees were seriously damaged.
Second, the factors affecting frost
1) Topography and topography. The higher the latitude and altitude of the
orchard, the lower the temperature and the heavier the frost; the lower the
terrain, the heavier the frost; the buffer around the river and the lake due to
the water temperature, the frost is light or does not occur frost.
2) Variety. There is a certain difference in anti-frost ability between
varieties, depending on the frost to light: Guoguang, Golden Crown, Fuji, Green
Banana, Indian, Marshal. In the Marshal Department, Aspen's ability to resist
frost is strong. Even if the center flower is frozen, it can still be harvested
because of its strong ability to bear fruit.
3) Organs. The anti-frost ability of each organ of apple tree is quite
different; in the same flower, the stamen is less resistant to low temperature
than the pistil, and the stigma is frozen at -1.5 °C, and the seed is less
resistant to freezing.
Critical temperature of each organ frost.
Flower bud period is -3.8~-2.8°C
Flowering period is -2.2~-1.6°C
Young fruit period is -2.2~-1.1°C
4) The height of the crown. The different heights of the canopy are
completely different from the frozen condition. The closer to the ground, the
heavier the frost, and the freezing damage is reduced with the increase of the
crown. For example, in the spring of 2017, in the investigation of a peach
garden in Fengrun County, Hebei Province, the freezing rate of flower buds below
1 m was more than 70%, and there was almost no freezing damage at 1.5 m.
According to reports, the freezing rate of apple blossoms is 70%~80% of the main
branches (below 1m), 30%~40% of the main branches of the second layer, and only
10%~20% of the main branches of the third layer. Therefore, in the fruit area
where the frost occurs frequently, it is possible to reduce the degree of frost
by appropriately increasing the height of the result portion.
5) Azimuth. The crown has different degrees of frost in different directions.
According to reports, the average rate of flowers on the windward (north)
surface of the new red and green banana crowns is 56.2%, and the leeward (south)
surface is only 20.9%.
We produce against frost candles for fruit farmers all year round. Our customers will book anti-freeze candles in October of each year and receive them in March-April. If you need to use against frost candles urgently, we also have
stocks for sale. Please feel free to order our anti-freeze candles. As a
professional against spring frost candles manufacturer, we will provide the best
service and will not delay for your use.