Some anti-freezing measures you may not know
Citrus contains a large amount of citric acid for vitamin C protection, with
Shunqi, cough, stomach, phlegm, swelling, pain relief, soothing liver and regulating qi and other effects, so it is a good traditional Chinese medicine.
Citrus is the most important fruit tree species in southern China with long life, high and stable yield and high economic benefits. It plays an important
role in the rural economic development of fruit farmers to get rid of poverty and become rich.
Citrus is a small evergreen tree or shrub about 2 m high. Branchlets thinner,
glabrous, usually spiny. Leaves long ovate-lanceolate 48 cm long. Flowers yellow-white solitary or clustered axillae. Fruit flat spherical diameter 57 cm orange-yellow or orange-red peel thin easy to peel. It blossoms in spring and ripens in October and December. Sex like warm and humid climate, cold resistance than grapefruit, lime, orange slightly stronger. Citrus genus Rutaceae Citrus subfamily is a tropical and subtropical evergreen fruit tree (except Aurantium trifoliate) used for economic cultivation. There are three genus Aurantium,
Citrus metal and Citrus metal. Citrus is mainly cultivated in China and other countries in the world.
In winter, the temperature is low, and if the citrus trees are not properly managed, there will be freezing injury. If the citrus branches are dry, the surface layer will crack or the whole plant will freeze to death. Therefore, it is one of the important measures to prevent freezing in citrus orchards. So how to prevent citrus from freezing in winter?
1. Selecting good soil conditions and strengthening cultivation
Soil is the base of citrus. The depth and weight of the soil layer have a
great influence on the cold resistance of citrus trees. Its roots are deep and leaves are lush, and its cold resistance is enhanced. Improve the soil fertility and water condition of citrus. Appropriate close planting, moderate fruit.
Appropriate close planting can not only benefit early but also alleviate the freezing injury of citrus orchards. Our city belongs to the northern margin of
citrus cultivation, which promotes soil transplanting, large seedling planting,
Dwarfing, and dense planting. In this way, the results can be early, benefit
before the periodic freezing injury, and also benefit the temperature of citrus
orchards. Control autumn shoots in time to avoid frozen late autumn shoots which
are not full. At the same time, when the soil temperature has not decreased,
apply enough base fertilizer to promote the recovery of tree vigor and enhance
cold resistance. The pests and diseases harmful to citrus leaves, branches and
trunks should be carefully controlled so that the tree body has enough organs
(leaves and strong branches) to produce nutrients to resist the cold attack.
2. Frost-proofing by covering film
Covering the plant with a film is also a good antifreeze method. Covering the
film can reduce certain cold wind, reduce evaporation consumption of plant
water, and also has a good thermal insulation effect on the soil layer. But it also has its shortcomings. The film is close to the blade, the permeability is poor, and the blade is easy to burn on sunny days. So many of them will use the support when using this technology, which is equivalent to building a small greenhouse.
3. Shelter protection: For low-lying and frozen-prone varieties and young trees, besides the main straw baling, the whole tree shelter can also be used to prevent freezing. When building a shed, besides ventilating and ventilating to the sun, the upper part and other three sides should be tightly covered. The whole tree can also be covered with an agricultural film to make it a
greenhouse. When the temperature rises, the agricultural film should be removed immediately so as not to burn the leaves or plants when the temperature is too high.
4. Drought orchards, 15 days before low-temperature freezing, if you have the conditions, ditch for irrigation, sprinkle crown water when frost falls, expand water and keep warm to alleviate frost damage. Before the advent of low temperature, spraying Paclobutrazol on the tree crown can reduce the heat loss and freezing damage of the tree. Before the freezing, through tillage and land preparation, garden mulching, reduce soil temperature, protect roots from freezing injury, and cover with soil.
Cover the canopy and wrap the young tree in the grass to prevent frostbite of branches and leaves. Then whiten the trunk of the tree and prepare whitening
agent with 5 kg lime + 10 kg water + 0.5 kg salt + 0.1 kg sulfur + fungicide.
The trunk is whitened about 60 cm in December. The exposed trunk and wound should also be whitened to protect the main branch of the trunk. Protect the tree body to prevent frost. Finally, use firewood, grain husk, sawdust, dried
orange, etc. to make about five smoke piles per mu, ignite and burn smoke before a cold wave or frost fall, so as to form smoke curtain over the orange orchard, raise
radiation frost, and at the same time, directly increase the temperature of
orange orchard and alleviate frost damage.
5. Select cold-resistant varieties and rootstocks. Wenzhou mandarin,
vermilion orange, touch orange, local early orange, early orange, and milk orange have strong cold tolerance, vanguard orange, Jinjin orange and navel
orange in sweet orange has strong cold tolerance, while summer orange and
Xinhui orange has weak cold tolerance. There are abundant rootstock resources of Citrus in China. Except for trifoliate orange, the hybrids of Yichang orange,
trifoliate orange and orange have strong cold resistance.
6. Anti-frost candles
When citrus is frozen in low temperature in winter, anti-frost candles can be
ignited in the orchard, which can raise the temperature of the orchard by 2-3
degrees. However, it should be noted that there is a certain distance between the anti-frost candles and the plant.