2. Soil conditions: Citrus has high requirements for soil. Generally speaking, the shallow layer affects the growth of citrus root system, which requires the soil depth to be at least 80 cm and the living soil layer to be above 60 cm. Citrus has strong adaptability to soil, but loam and sandy loam are the most suitable soils for citrus growth. Strong cohesive soil and sandy soil need to be reformed. Soil ph value affects the availability of soil nutrients, and the soil pH value is 5.5-7.0. The slope of the orchard is less than 25 degrees. When planning a garden, there should be necessary roads, irrigation and drainage, water storage and ancillary building facilities. In terms of specific planning, we should concentrate on one place as much as possible and build gardens in places with good traffic and water conditions.
3. Planting density, the most common spacing in citrus cultivation is 4x6m, but different planting methods tend to make citrus grow densely in the later stage, so 4x3m or even 4X 1.5 spacing is often used. Its planting density is usually 4 10 plants per hectare, and there are 800 plants or even 1600 plants per hectare in the case of close planting.
4, reasonable pruning, generally pruning needs different pruning methods in different periods of citrus trees.
(1) vegetative growth period: on the basis of fixing stem and shaping seedlings, the crown is mainly shaped and cultivated, and the main branches and auxiliary branches are continuously cultivated in the first 1 and second year after planting, and the side branches are matched, so that the tree body is compact and the branches are flourishing. Cultivate shoots 3 ~ 4 times a year, form a crown as soon as possible, and remove buds in time.
(2) Growth and fruiting period: continue to cultivate the crown and bear appropriate fruits. Promote new shoots 2 ~ 3 times a year, so that the branches are evenly arranged and a compact crown is formed as soon as possible. The middle and upper parts of plants do not bear fruit or bear little fruit during the day, and pruning is mainly based on bud wiping and shoot control.
(3) Full-fruit period: the height of the tree is generally controlled below 250cm, the crown is wide, the periphery is concave and convex, the branches grow healthily, the thickness of the green leaf layer should be above 100cm, and it is ventilated and transparent, resulting in a three-dimensional effect. Control the intersection between rows, and the crown coverage rate is 75% ~ 85%. Pruning suitable trees, deleting secrets and keeping sparse, removing the weak and keeping strong; Cut and stay, cut outside and stay inside; Cut down more trees and plant more flowers, and cut down less trees and plant less.
(4) Aging period: Retracting pruning, renewing or thinning old fruiting branches, forcing new fruiting branches in the inner chamber or lower part to sprout, keeping tillering, keeping intensive pruning, balancing arrangement, spending more flowers and cutting more, and properly pruning weak trees.
5. Fertilizer and water management. Generally speaking, our fertilization principles for citrus fertilizer and water management are: to fully meet the needs of blood oranges for various nutrients, advocate more organic fertilizers, and rationally apply inorganic fertilizers and formula fertilizers. According to the results of leaf analysis, orchard soil analysis and blood orange phenology, fertilization is guided. We usually use fertilization methods: mainly soil fertilization, combined with foliar fertilization. The methods of annular furrow application, strip furrow application, hole application and soil surface fertilization were adopted. You can decide according to your actual situation.
6, pest control, several common diseases of citrus: Huanglongbing, canker, scab. Citrus Huanglongbing is a devastating disease. Once it happens, there is no cure. Must be cut down in time, and sprinkle hydrated lime powder in the diseased hole for disinfection. Citrus Huanglongbing spreads the virus through psylla. In the process of citrus growth, timely use of bifenthrin such as thiamethoxam, acetamiprid, pymetrozine, nitenpyram, imidacloprid, veratrine, phenoxy, buprofezin and carbosulfan to control psylla can reduce the disease.