Detailed Explanation of Scientific Planting Methods and Techniques for Longan Trees
How are longan trees scientifically planted? How should longan trees be managed? We ask experienced netizens to help introduce this. Longan, also known as guiyuan, has the effects of tonifying the heart and spleen and nourishing the blood to calm the mind, and is a well-known bulk medicinal and edible delicacy. It is mainly produced in Fujian, Guangdong, Guangxi, Sichuan and Taiwan, China, and other places. Zhongdiwang has compiled the scientific planting of longan...
How are longan trees scientifically planted? How should longan trees be managed? We ask experienced netizens to help introduce this.Longan, also known as guiyuan, has the effects of tonifying the heart and spleen and nourishing the blood to calm the mind, and is a well-known bulk medicinal and edible delicacy. It is mainly produced in Fujian, Guangdong, Guangxi, Sichuan and Taiwan, China, and other places. Zhongdiwang has compiled the scientific planting methods and management methods for longan, listed in detail below for netizens' reference.
Longan planting methods
1.Selection of longan planting site:When planting longan,it should be chosen in a mountainous area with sufficient sunlight, good air circulation, deep soil layers (red soil, sandy soil or clay soil is best, with a pH value of 5-6 and organic matter content above 2%), no freezing damage and wind damage, and a slope below 15 degrees, preferably with a sufficient water source available nearby for use.
2.Preparation of longan planting holes:To create a deep rooting soil layer for longan - dig large planting holes and press in fertilizer to improve the soil. For newly planted longan, large planting holes of 1 m x 1 m x 0.8 m should be dug, and 10 kg of green manure, 30 kg of organic fertilizer mud and 0.5 kg of quicklime should be placed in them, with 10-15 kg of decomposed poultry and livestock manure placed in the upper layer, and a certain amount of topsoil backfilled. Only after 2-3 months of composting and maturation can planting be carried out, making the planting holes fertile and deep, rich in organic matter and good in air permeability, laying a good foundation for the growth of longan.
3. Setting up drainage and irrigation ditches for longan:On both sides of the main and trunk roads of the marked longan planting holes, vertical water ditches 50-60 cm deep and wide should be dug, connected in the middle with the back ditches and horizontal drainage ditches of terraces at all levels. To reduce rainwater erosion, the vertical water ditches should be built in a bamboo-joint shape or have weeds growing at the bottom of the ditches. For every 15-20 mu, set up one water storage pond and one fertilizer water pond each of 3 m x 5 m x 1.5 m, to facilitate irrigation, pesticide application and composting of fertilizer water.
4. Longan planting and planting period:Planting can be carried out according to the characteristics of the longan variety. Generally, 15-30 longan plants are planted per mu. Do not blindly pursue dwarfing and close planting.
The planting time is around Qingming Festival when the temperature rises or before the spring shoots sprout. The planting depth is related to the seedling stage. For air-layered seedlings, the soil covering depth should be about 5 cm higher than the original soil ball. Never plant too deep or trample with great force, which can cause root breakage. After planting, water each plant with 10-15 kg of settling water.
Longan tree management methods
Fertilization of young longan trees : Fertilization can be carried out 1 month after longan trees are planted. It is recommended to implement "two fertilizers per shoot", that is, apply the 1st fertilizer when the terminal bud of the branch shoot begins to sprout; apply the 2nd fertilizer when the new shoot has basically stopped elongating and the leaf color changes from red to green. In addition, apply winter fertilizer mainly based on organic manure in November-December each year.
For the 1st new shoot fertilizer in the 1st year, apply 15 g each of urea and sulfur-containing compound fertilizer per plant each time, or apply 2-3 kg of 10% urea or 30% decomposed human excrement and urine liquid. Thereafter, the amount of fertilizer for each new shoot gradually increases, increasing by 20%-30% for each new shoot. From the 2nd year onward, the fertilization amount for each new shoot increases by 15%-20% compared with the previous time.
Generally, fertilization is done by opening 3-4 shallow holes or a shallow ring ditch at the outer edge of the longan tree root zone, applying the fertilizer in the holes or ditch, and covering with soil after application. In the dry season, liquid fertilizer is better. At the same time, 0.2%-0.3% potassium dihydrogen phosphate solution can be applied together with pesticide spraying.
Pruning of young longan trees: In the 1-3 years after planting, longan trees are mainly pruned lightly. At a trunk height of about 30-50 cm, cultivate 3-4 main branches that are evenly distributed and grow vigorously. Afterward, the main branches naturally extend, and overly dense branches and diseased and pest-damaged branches are cut off, so that a three-dimensional fruiting canopy is formed.
Fertilization of fruiting longan trees:
1. Longan flower-promoting fertilizer: generally applied from December to before February of the following year. Calculated for a tree bearing 10 kg of fruit, apply 200-250 g of sulfur-containing compound fertilizer, 100-150 g of urea, 200 g of raw bran powder, 400-500 g of superphosphate plus 10-20 kg of poultry and livestock manure (mix and compost for 1 month before application); combined with winter orchard cleaning, apply 1-1.5 kg of quicklime per plant.
2. Longan fruit-strengthening fertilizer: after flower drop and before the 1st physiological fruit drop, calculated for 10 kg of fruit, apply 100-200 g of urea, 200-250 g of compound fertilizer and 250-300 g of potassium chloride per plant;
3. Longan pre-harvest fertilizer: apply before the end of June. Estimated for 10 kg of fruit set, apply 200 g of urea and 250 g of compound fertilizer per plant.
4. Longan tree shoot-pushing fertilizer: during the growth period of summer shoots and autumn shoots after fruit harvest, calculated for a tree that can bear 10 kg of fruit, first apply 200 g of raw bran powder and 10 kg of decomposed poultry and livestock manure within 7 days after fruit harvest; then apply fertilizer once each when the new shoot of each flush begins to sprout and when the new shoot begins to turn green, applying 100-200 g of urea per plant.
5. Longan tree fertilization method: open holes or ditches at the drip line of the canopy. Fertilizers such as urea and compound fertilizer that easily move to the lower layer should be applied shallowly, with holes 5-10 cm deep; organic fertilizer and phosphate fertilizer should be applied deeply, with holes 20-30 cm deep. In dry seasons, liquid fertilizer should be applied, covered with soil after application, and the positions should be rotated each time.
Watering of longan trees:
1. Before flowering (after autumn shoots mature to the late stage of flower bud differentiation), keep the soil relatively dry.
2. From the flowering period to the autumn shoot sprouting period, keep the soil moist and the water supply balanced. Irrigate (or sprinkle water) in case of drought, and promptly drain accumulated water in case of rain.
Methods for controlling shoots and promoting flowers in longan trees:
1. Before winter shoots sprout (between Major Cold and Minor Cold), carry out girdling treatment on trunks about 8-10 cm in diameter.
2. For new shoots that emerge after November, remove them manually when the new shoots are below 10 cm, or spray and kill them with ethephon solution or other shoot-killing chemicals when they are below 5 cm.
3. For fruit trees that may sprout winter shoots but have not yet sprouted, spray paclobutrazol in mid-to-late December to inhibit winter shoot germination.
Methods for strengthening flowers and preserving fruit in longan trees:
1. Ring-cutting or short-cutting flower spikes, delaying flowering time to avoid flowering in rainy weather;
2. Spraying compound nucleotide fruit-preserving agent during the flowering period to increase fruit set rate and prolong the flowering period;
3. Placing bees during the flowering period to attract flies, shaking flowers after rain, spraying water in dry weather, artificial pollination, etc.
Pruning methods for fruiting longan trees:
Longan trees are generally pruned in autumn and spring. Autumn pruning is in the previous July-September, and spring pruning is carried out after "Beginning of Spring" when white flower bud points appear. The main targets of pruning are cutting off overly dense branches and diseased and weak branches. The pruning amount is based on allowing a small amount of scattered light to reach the ground, and the pruning amount each time should not exceed 15% of the total branch amount.
Winter management methods for longan trees
Control methods for longan tree eriophyid mites