In December, when citrus is planted, winter fertilizer should be applied like this.

Dielianhua Ailiao Agrochemical

Recently, many fruit farmers in the WeChat circle asked when winter fertilizer for citrus fruit trees and young trees should be applied? What fertilizer is good?

1. What is winter fertilizer

The so-called winter fertilizer, as its name implies, is a kind of base fertilizer applied in winter, including farm manure, biological organic fertilizer, chemical fertilizer, etc.

Winter fertilizer is usually applied before and after fruit harvest. However, a lot of time and personnel need to be arranged before and after fruit picking to harvest and sell fruits, and the workload of applying organic fertilizer into ditches is relatively large, which requires more time. After fruit picking, garden cleaning and proper pruning may also be arranged.

Therefore, winter fertilizer application should be arranged reasonably according to the physiological conditions of citrus trees, terrain environment and soil characteristics, which will not affect fruit harvest, tree vigor recovery and flower formation in the coming year.

Second, why should winter fertilizer be applied

1. Winter fertilizer-fruit picking fertilizer (also called month fertilizer) is conducive to restoring tree vigor as soon as possible, has good leaf protection function, prolongs leaf life, prevents citrus leaves from falling in winter, ensures stable yield and high yield of orange trees, and improves quality.

2. The winter fertilizer organic fertilizer applied to the soil plays a role in keeping warm and protecting the roots in winter, and slowly decomposes under the activity of microorganisms, which is conducive to the gradual absorption and utilization of citrus in the case of slowing growth in winter and weakening the absorption capacity of roots, so that more organic nutrients are accumulated in the tree body for the needs of germination and flowering in the coming year.

3. Furrowing and root cutting, and promoting flower bud differentiation in winter.

Third, what kind of fertilizer is mainly applied to winter fertilizer

Organic matter-rich soil is very beneficial to citrus roots, robust and lush roots are the guarantee of citrus yield and quality, so it is necessary to keep the soil loose and rich in organic matter. According to experience, citrus can have high and stable yield only when the content of soil organic matter in root area is above 2%. Therefore, the soil foundation is relatively thin should increase the input of organic matter when applying base fertilizer in autumn and winter.

Orange winter fertilizer is mainly organic fertilizer, and quick-acting chemical fertilizer and medium and trace element fertilizer are appropriately added. Organic fertilizer must be fully decomposed, organic fertilizer that has not been decomposed is easy to burn roots after deep burial; chemical fertilizer and medium and trace element fertilizer should not be excessive, excessive fertilization is easy to occur reverse osmosis phenomenon, causing orange orchard branches and leaves to dry in winter, resulting in defoliation.

Apply medium and trace element fertilizer according to local conditions. The orange orchards in red and yellow loam soil of southern China are acidic, and the contents of available elements such as Ca, Mg, Zn, Mn and B are relatively low. According to the different conditions of orange orchard, winter fertilizer should be applied to supplement the deficiency of trace elements.

IV. When to apply winter fertilizer

Chinese citrus is suitable for a wide range of areas, latitude across a large, winter minimum temperature difference is very large. Organic fertilizer can be buried and applied at any time in winter in southern citrus areas, even in the coldest period of the year (winter solstice to severe cold), so as to achieve the purpose of eliminating underground pests in combination with ploughing, generally applied during the period from mild cold to severe cold.

For winter cold areas to strive for early organic fertilizer, strive to complete the application before the root dormancy.

For fruit trees with sugar orange hanging, if the fruit amount is moderate, the tree is strong, the leaf color is thick green, the fruit will be dug and injured if it is not fertilized before harvest, and it will be difficult to operate because of the existence of obstacles such as struts, etc., and the fertilization before harvest may lead to the degree of fruit color change out of control. Therefore, if there is no experience, it is best to apply winter fertilizer after harvest.

It is generally recommended to immediately supplement foliar fertilizer after fruit picking in combination with garden clearing, so as to restore tree vigor as soon as possible, and then consider enlarging holes and burying winter fertilizer.

In addition, for hanging fruit trees with large number of fruits and relatively weak tree vigor, it is advisable to apply a small amount of quick-acting chemical fertilizer one week before fruit picking to supplement plant nutrients, while the time of applying base fertilizer (organic fertilizer) should be placed before the cold season.

Pre-harvest support trees are not conducive to winter fertilizer application--

5. Correct fertilization methods

The following methods can be used for winter fertilizer application of general fruiting trees:

Fertilizing holes, ditching do not hit the same direction and position every time, to rotate the direction and position one after another.

Due to the fertility of the root system, the fertilizer application position of citrus should be slightly deeper or farther than the concentrated distribution position of the root system. The late-effective organic fertilizer in winter fertilizer should be deeply applied, ditching 30-40 cm above, outside the drip line, to induce the root system to develop deeper and wider, expand the absorption range of nutrients, and enhance the resistance of the tree.

Winter fertilizer should be applied deeply in citrus orchards in paddy fields, and the bad habit of shallow application in pan shape should be changed. Meanwhile, attention should be paid to ditching, drainage and intertillage to improve soil aeration. Heavy fertilization should be emphasized in citrus orchards with thick clay soil, and frequent and thin fertilization should be applied in sandy soil.

The fertilization sequence is to put organic fertilizer first after trenching, then spread chemical fertilizer and medium and trace element fertilizer on the excavated soil, fill the pit with soil, avoid direct contact with root groups.

6. How to fertilize fruit trees

Winter fertilizer is mainly decomposed organic fertilizer, which can be fermented farm manure, peanut bran or high-quality biological organic fertilizer, matched with appropriate amount of nitrogen, phosphorus, potassium and medium and trace element fertilizer, and buried in deep ditch.

■ Trees put into production next year, apply 2 - 3kg Mengding base fertilizer or Mengding strong + multi-control fertilizer 2-3 liang +9 elements 2-3 liang for each plant.

■ Fruit trees, according to the yield of 50 kg plants, each plant applied Mengding base fertilizer 3 - 5 kg or Mengding strong + multi-control fertilizer 5-8 liang +9 element fertilizer 3-5 liang.

7. How to fertilize young trees?

In winter, the absorption capacity of roots is weaker for young plants. Fertilization should be applied before the arrival of extremely cold weather after winter, generally from early December to late January next year. Depending on the weather conditions, the average temperature below 15℃ is more appropriate to prevent premature burial of winter fertilizer, warming easy to sprout winter shoots, and at the same time play a role in heat preservation and cold resistance.

The last batch of young trees whose shoots are not mature can be washed with Mengli 28+ Oxfam high-potassium water-soluble fertilizer, and sprayed with super phosphorus and potassium + solution on the leaves to promote aging and prevent freezing damage.

Winter fertilizer buried application, generally in the crown drip line outside the ring groove or both sides of the groove, 1-2 years old trees, each plant application Mengding base fertilizer 2 jin or Mengding strong + nine elements 1-2 liang + feed stable multi-control fertilizer 2 liang.