Planting techniques of Maogu mandarin

Maogu tangerine is a hybrid of wide-skinned orange and sweet orange bred in the United States in 1913. Lin Pu, a professor of horticulture at National Taiwan University, introduced it to northern Taiwan in the 1970s because of its high sugar content, good flavor, thin and juicy skin and later ripening than banana orange. the cultivation area has increased year by year, and in recent years, southern Fujian has also been introduced and planted. Let's take a look at the planting techniques of Maogu mandarin.

Planting technology

Choose loose, fertile, good drainage and irrigation, pH5.5~6.5, leeward and sunny slopes or paddy fields as gardens. According to the planting specification of row spacing 3 × 2m, 111plant / mu or row spacing 2.5x2m, 133plant / mu, dig pits or trenches 80cm wide and 60cm deep, put 50kg retted organic fertilizer and 1kg calcium magnesium phosphate fertilizer in each pit. Green manure (weeds) 30,50kg was mixed with the soil and returned to the pit about 30cm above the ground, and it was planted before sprouting in spring and 15 days after the Beginning of Spring. At this time, the root has begun to move, and the survival rate is high. In areas with good irrigation, autumn planting is also possible. After planting for about a month, the seedlings basically survived, applying some thin dung water plus 0.2-0.5% urea or compound fertilizer. In the future, the fertilizer of attacking and strengthening shoots were applied before the germination of new shoots and before the ripening of branches, and the fertilizer was mainly available fertilizer.

Crown culture

Maogu mandarin has strong shoot ability and often grows in clusters. If it is not controlled, it will inevitably lead to insufficient supply of tree nutrition, poor growth and development of branches, short and weak, shaded and susceptible to diseases and insect pests. Therefore, wiping and shaping, cultivating a ventilated and transparent crown with reasonable distribution of branches is the key to the stability, high quality and high yield of the tree. Generally strong branches leave only 3 or 4 shoots, and ordinary branches leave 2 or 3 strong buds in different directions. There are 3 groups of shoots in spring, summer and autumn in Guilin every year, and 3 to 5 batches in the south of Liuzhou, gradually forming a compact and robust crown.

Fertilizer and water management

Maogu citrus has many flowers, easy to set fruit, high yield and high solid content, so the management of fertilizer and water is very important. We sum up the management of this part into three sentences: "Spring nitrogen, summer potassium and autumn compound, bran water drenching during expansion, and heavy application to promote recovery after harvest." "Spring nitrogen" means that after the beginning of spring and before the bud germinates, the root system begins to move, mainly nitrogen fertilizer, applying fertilizer for attacking tips and flowers, and sprinkling 25 kg of retted organic fertilizer and 0.5 kg of urea under each tree crown, gently loosening the soil and turning the fertilizer under the topsoil. "Summer potassium" refers to the first ten days of May, before the physiological fruit drop, mainly potash fertilizer, stable fruit fertilizer. Spraying 0.3% potassium dihydrogen phosphate on the leaf and 0.2 kg potassium chloride per plant on the ground can reduce fruit drop. "Autumn compound" is the application of 0.2 kg / plant compound fertilizer before autumn shoots are released in mid-July. "Bran water" refers to the period from July to the first ten days of December. sprinkle with light bran water and 0.1% 0.2% urea every half month, about 25 kg per plant, "postharvest re-application", that is, after harvest. Dig trenches 40 cm wide and 60 cm deep along the 1x4 crown dripping line. Each plant is treated with 20 kg of fresh grass, 30 kg of compost organic fertilizer and 1 kg of calcium superphosphate.

Shaping and pruning

The shaping and pruning of Maogu citrus seedlings can be summarized into four sentences: "keep spring shoots as appropriate, erase summer shoots, unify autumn shoots, and strictly control late autumn shoots and winter shoots." That is, when the spring shoot grows to 5cm long, there are 2 or 3 strong buds in different directions on each shoot. The principle of leaving buds is: sparse and sparse, short and long, weak and strong, too strong branches, leave 6 or 7 leaves to pick the heart, wipe off all summer shoots, before autumn shoots (early and middle July), wipe off scattered buds, short shoots, truncated positions should not be too high or too low, preferably between sections 6 to 7. If the tree is weak or the tree shape is not compact, you can leave a small amount of late autumn shoots according to the situation, and all the rest and winter shoots will be erased. In winter pruning, on the basis of ventilation and light, reasonable distribution of branches and tight crown, cut off the cross branches, shade branches, long branches, disease and insect branches, weak branches and withered branches, burn them and clear the garden at the same time.

Protect flowers and fruits

1. Flower thinning and fruit thinning: due to the many flowers and high fruit setting rate of Maogu citrus, it is easy to cause insufficient nutrition supply, poor growth and development of flowers and fruits, small fruit and poor quality, and it is also easy to cause the phenomenon of annual fruit. Therefore, it is necessary to remove some flowers and fruits. The practice is weak flowers and weak fruits, diseases and insect pests, flowers and fruits, no leaves, few leaves, flowers and fruits are all erased. When the flowers are white, spray 500-fold liquid trichlorfon on the ground and 800-fold liquid fenpropathrin on trees to control bud maggots and thrips.

2. Wind and sunscreen: the fruiting part of Maogu mandarin is mostly at the top of the branches, which is easy to cause sunburn scars, especially for young trees. Therefore, when the transverse diameter of the fruit is up to 4 cm, stick white paper or bagging in the sunny part, which can reduce the damage of sunburn. Although Maogu mandarin has strong cold resistance, serious frost and snow freezing will still affect the fruit quality and yield, so irrigation, mulching and smoking before and after frost and snow, as well as spraying foliar fertilizer such as plant dragon, have a certain protective effect.