Management techniques of Citrus Orchard in Winter

Management techniques of Citrus Orchard in Winter

In winter, citrus trees enter a relatively dormant period, and their physiological activities are relatively weak, which is a good time for us to disinfect orchards and sterilize insects. At the same time, after a year of growth and fruit, citrus trees consume a lot of nutrients, and the trees are weak and need to be replenished in time. If we want to have a good harvest next year, we must do a good job in the management of citrus orchards in winter.

1 Prophase management of citrus orchard

1.1 increased application of pre-harvest fertilizer

Multiple compound fertilizer + farm manure was applied once in the first and middle of October to improve tree nutrition level, enhance tree resistance and ensure normal differentiation of flower buds.

1.2 strengthen the control of diseases and insect pests

From mid-late October to mid-November, spraying 600-fold Dasheng M45 or 600-fold mancozeb twice on the orchard and paying attention to the control of red and yellow spiders is the key to reduce the occurrence of diseases in the later stage.

1.3 rational use of plant growth regulators

In orchards that want to keep trees fresh, spray 2mem4-D 30~50mg/L once when the fruit changes from dark green to light green, usually in the middle and last ten days of October to reduce fruit drop in winter. The second ten days of November and the last ten days of December were sprayed with 2jin4-D30~50mg/L respectively.

1.4 Prevention of fruit freezing injury

In the area where the winter temperature is below 0 ℃, the fresh-keeping and storage of fruit is easy to suffer frost damage, so it is not suitable to carry out. When the citrus fruit is really lower than-3 ℃, there will be serious freezing injury. In occasional areas, according to the weather forecast, film mulching and smoking can be used to prevent frost. Before the frost in late November, the canopy was covered with white transparent plastic film to reduce the fruit shedding caused by low temperature. When the temperature rises to about 12 ℃ (usually from the end of February to the beginning of March), the film should be uncovered in time. Reduce fruit drop and rotten fruit caused by disease and insect breeding, spray fungicide once after uncovering the film.

(2) late management of citrus orchard

2.1 maintain soil moisture

Due to the drought in winter, the fruit is easy to lose water and fall off, so it should be irrigated in a timely and appropriate amount. At the same time, to strengthen soil moisture, the canopy dripping line can be covered with rice straw or film, and the straw thickness 3~5cm [Yoshama Huayao].

2.2 increase application of spring fertilizer

It was carried out in the middle of February to quickly restore the tree potential and promote shoots and flowering. It is not suitable to pick fruit within 20 days after fertilization, so as not to reduce the fruit quality.

2.3 apply good fruit-picking fertilizer

After fruit picking, it is necessary to apply fertilizer in time to supplement the nutrients taken away by the fruit and restore the tree potential. Generally completed in December, the main type of fertilizer is organic fertilizer, each plant is applied human and animal manure 25~50kg, citrus special compound fertilizer 2~3kg. Soil irrigation is combined with irrigation when the soil is dry. The fertilizer hole was excavated outside the drip line of the crown, deep 50cm, wide 20cm, and cover the soil in time after fertilization.

2.4 ploughing the soil of citrus orchards

One ploughing of the whole garden is generally carried out in winter to improve the soil structure, reduce water evaporation and freezing injury in winter, remove litter and reduce the breeding of diseases and insect pests. Ploughing time should be early to avoid poor healing after low temperature root injury. The soil outside the drip line can be turned deeply, that is, 20~30cm, and the soil within the drip line should be shallow ploughed, that is, 10~15cm, to avoid root damage.

2.5 reasonable pruning

The purpose of pruning is to improve the ventilation and light transmission condition of the tree and adjust the nutrient balance of the tree. In general, a simple pruning method is used to remove 1 or 2 large branches that affect ventilation and light transmission of the tree, and then cut off disease and insect branches, weak branches, withered branches, overgrown branches, fruit handle branches, retracted cross branches, overlapping branches and drooping branches. Pay attention to the cultivation and renewal of the fruiting branch group to maintain the continuous high yield of the tree.

3Prevention and control of diseases and insect pests

Fruit growers should make use of the winter leisure season to carry out a thorough control of the citrus orchard, specifically do a good job of four words: clear, turn, paint, spray. Remove disease and insect branches, remove fallen leaves, withered branches and residual fruit, concentrate on burning, and turn the soil to kill the larvae or pupae of overwintering buds maggots, weevil and other pests in the soil. The trunk was painted white and the spraying time was carried out after fruit picking or before spring bud germination in February. The agent can choose 1 ~ 1.5 °be stone sulfur mixture or oil emulsion 60% 100 times to kill overwintering mites, scale and some bacteria. At the same time, it should be noted that the interval between the use of stone sulfur mixture and oil emulsion is more than one month to avoid drug damage.