According to the natural geographical conditions and market economic benefits of our city, "Gan Lu" and "American navel orange" should be the first choice for planting citrus. "Gan Lu" is the main variety in southern Fujian, and it is listed as one of the top ten citrus varieties in China, and it is a brand with relatively competitive export. American navel orange is an early introduced variety, which is deeply loved by consumers because of its large and beautiful fruit, early maturity and excellent quality. It is an excellent citrus variety with stable market and good economic benefits.
The second is reasonable planning and high standard garden construction.
1. According to the characteristics of citrus ecological environment, which is cloudy, humid and calm, the following points should be paid attention to when building a garden:
(1) The slope of hilly land should be below 25 degrees, and the sandy soil with deep soil layer, soft core soil structure and easy water and air permeability is better. If the physical and chemical properties of soil are poor, it should be improved.
(2) Because of the strong sunshine in summer and autumn and the lack of rain in our city, it is not suitable to build a garden in the west. If conditions are limited, shelterbelts should be established.
(3) The garden should be built in a place with sufficient water resources and no flash floods or accumulated water.
2. Planning: divide communities according to local conditions, rationally design inter-garden roads, operation roads and flood drainage systems, build shelter forests, and arrange buildings for scientific allocation planning.
3. Terrace construction: In order to maintain soil and water and facilitate management and operation, it is necessary to build terraces with the same height. Its method is mainly to clean up the site and measure the base point and contour line (which can be installed by soil method). The width of terraced fields should be determined according to the slope. For example, the width of terraced fields of 20-25 degrees is 3.5-4 meters. The smaller the slope, the wider the mesa.
Third, make preparations before planting and increase the number of plants.
1, dig a big pit and apply a big fertilizer. The planting hole is 0.8×0.6 m deep and 0.8×0.6 m wide, and then the screened urban garbage, other livestock manure 1-2 tbad, weed green material and lime 1-2 kg are applied, which are evenly mixed with the core soil and then backfilled into the hole; In order to prevent subsidence, the backfill soil should be 10-20cm high.
2. Select seedlings and plant them in time: select the grafted annual seedlings, transplant them with soil as far as possible, and trim the redundant crown branches appropriately. The most suitable planting time in our area is from February to March in spring, when the spring buds have not germinated. Orchards with convenient irrigation can also be planted in late autumn, which is beneficial to the early development of the following year. Citrus and navel oranges can be planted with 50-60 plants per mu, and it is better to plant them closely and with wide row spacing. After planting, you should water your feet and erect supports to prevent strong wind shaking from affecting your survival. Restore growth 20-30 days after planting, apply thin decomposed human excrement and urine once every half month to promote growth, and often prevent and control pests and diseases, uniformly release bamboo shoots and cultivate the crown.
Fourth, pay attention to land reform and accelerate soil maturation.
The purpose of soil management is to make the soil mature and create water, fertilizer, gas and heat conditions conducive to the growth of citrus. The main methods are:
1. Deep ploughing, hole enlargement and application of organic fertilizers, such as garbage, crop straws, green manure and livestock manure, are carried out when citrus is young.
2. Intercropping young green manure crops such as legumes between rows, and timely ditching and burying green manure and straw.
3. Tree tray mulching: In addition to green manure, crop straws, leaves and other materials can be used to keep moisture, stabilize ground temperature and increase organic matter.
4. Adult trees should pay attention to intertillage weeding, and herbicides such as glyphosate can also be used when weeding to improve work efficiency.
Five, master the law of fertility, scientific fertilization and water management.
Citrus is an evergreen fruit tree, which can grow all year round, with many branches and long fruiting time, and needs more fertilizer and water supply.
1, reasonable irrigation, our region is prone to drought in autumn and winter. When it is found that the soil with a depth of 5-20 cm cannot be kneaded into a ball after being broken (about less than 50% of the field capacity), irrigation is needed, and methods such as furrow irrigation infiltration, garden flooding or tree tray irrigation can be adopted. Conditional sprinkler irrigation facilities can be built to save water and increase efficiency.
2, scientific fertilization:
(1) Organic fertilizer is the main component, supplemented by chemical fertilizer, and the appropriate ratio is 3: 1. According to the needs of citrus growth and the nature of various fertilizers, rational use should be made. Generally, the demand ratio of citrus to nitrogen, phosphorus and potassium is 1: 0.5: 0.7. In addition, the lack of trace elements should also be supplemented.
(2) Fertilization period and dosage: Young trees should mainly use nitrogen fertilizer, with the goal of promoting growth and expanding crown, and it is better to apply nitrogen fertilizer in a small amount for many times. The annual fertilization amount of 1-3 years old can be 0.2-0.5 kg of pure nitrogen per plant every year, and it will gradually increase from less to more. You can control the smearing time before each shooting. The purpose of adult fruit-bearing tree cultivation is to promote many branches and fruits, maintain the balance of branches and fruits, and achieve high yield and high quality. Fertilization is mainly concentrated in four periods:
① Fertilizer for promoting buds and strengthening flowers was applied at the germination stage of spring buds, with nitrogen as the main fertilizer and phosphorus and potassium as the auxiliary fertilizer, accounting for 20% of the whole year. Specifically, 30 tons of human excrement and urine and 7.5 kg of urea were applied per mu.
(2) Applying fruit-protecting fertilizer, mainly nitrogen, combined with phosphorus fertilizer during the young fruit growth period, accounting for 65,438+00% of the annual fertilization.
③ Applying fertilizer for strengthening shoots and fruits in autumn shoot stage: combining quick-acting fertilizer with slow-acting fertilizer, that is, applying 30-40 loads of high-quality human excrement and urine per mu, adding 50 kg of decomposed cake fertilizer and urea 10 kg. Fertilizer consumption accounts for 35% of the whole year. After the new branches are self-sheared, topdressing the roots twice.
④ Before and after fruit picking, the base fertilizer was still combined with quick-acting fertilizer and after-effect fertilizer, and the fertilization amount accounted for 35% of the whole year. Calculated by manure, apply 60-80 loads per mu, with 50- 100 kg of lime.
Sixth, reasonable shaping and pruning to maintain high yield of trees.
1, young tree shaping:
(1) The seedlings were cut at the top and dried to cultivate seedlings with short stems and many branches. After the new shoots mature in summer, cut off the top 20-25 cm above the ground to make them branch.
(2) Bud smearing and bud control, that is, when new buds germinate after topping, sporadic and early-developing new buds are erased, and bud smearing is stopped when each plant has 5-6 buds; When the new branches grow to 5-8 cm, select 3-4 new branches with strong growth and uniform distribution as the main branches, and smooth the rest; When the main branch exceeds 18 cm, cut it short, and so on.
2. Prune the result tree
(1) Prune according to the growth and fruiting habits of different varieties. Citrus trees are tall and straight, and most of them bear fruit on the periphery of the upper crown. Therefore, in addition to pruning too dense twigs inside, the branches outside the crown should be cut less, while the branches inside and outside the crown of American navel orange can bear fruit, and the short fruit branches bear higher fruit. Therefore, pruning should be light, generally short branches are the main ones, and more thick and short branches (bearing mother branches) should be promoted.
(2) Pruning according to the growth and fruiting characteristics of different branches:
Spring shoots: those that grow well can become the mother branches of the next year or the base branches of summer and autumn shoots. Therefore, pruning should leave weak and strong, dense and even. Summer shoots: They last for a long time, and the tree shape is disordered. Excessive sprouting will aggravate the physiological fruit drop, so when they grow to 15-20 cm, they should be smoothed or cut short, so that 2-3 autumn shoots will sprout and become fruiting mother branches. Autumn shoot: the proportion of mature fruit bearing branches is high, and it should not be pruned, but it should be thinned if it is too dense. Winter bamboo shoots: insufficient growth consumes nutrients and should be erased as soon as possible.
(3) Different pruning methods should be adopted according to the tree potential and results. For stable trees with normal growth, the pruning degree should be light, only branches with pests and diseases should be cut, and the number of summer and autumn shoots should be properly controlled. Older trees should be pruned lightly, mainly by pruning, supplemented by short cuts, because they have more fruits and fewer branches in summer and autumn. Cultivate well-grown branches in spring, summer and autumn to make them the mother branches in the next year. For young trees, because of less fruit, strong trees and heavier pruning, short cutting combined with thinning should be adopted to reduce the flowers in the next year and lay the foundation for high yield in the next year.
Seven, seize the critical period, comprehensive prevention and control of pests and diseases.
There are many diseases and insect pests in citrus, which are serious. It is necessary to implement the plant protection policy of comprehensive prevention and control. Mainly grasp the following links:
1, clear the garden in winter to prevent overwintering pests and diseases. Because most of the pests and diseases that harm citrus spend their dormant period on fallen leaves or weeds, it is necessary to sweep away the burnt dead leaves and fallen fruits in winter and spray pesticides on the crown and surface to kill pests and diseases, so as to reduce the source of pests and diseases in the coming year.
2. Pest control in spring shoot stage. The spring shoot period is the initial stage of the occurrence of pests and diseases, mainly including scab, canker, red and yellow spiders and so on. For scab, 0.5-0.7% Bordeaux solution should be sprayed in spring bud and 0.3% Bordeaux solution should be sprayed in summer bud. In spring, when the canker sprouts, the old diseased leaves are cut off and sprayed with 0.5% Bordeaux solution or copper soap solution (1: 4: 400). For the prevention and control of red and yellow spiders, 20% dicofol should be sprayed 500-600 times in drought and 0.5 times mixture of sulfur or 500 times malathion in rainy days.
3. Insect control in summer and autumn. This period is a period of rampant pests and diseases, and the main targets should be rust ticks, red spiders, leaf miners, leaf rollers, aphids and scale insects. The breakdown is as follows:
Rust ticks: young trees are sprayed with a mixture of 0.2-0.3 sulfur and stones; Results 600 times solution of 8% zineb was sprayed for 2 ~ 3 times.
Starscream: spray dimethoate emulsion 1000 times and add 20% dicofol 600 times.
Deciduous moth: When most buds are one centimeter long, spray 1000 times of phosphate, 1200 times of autumn shoots or 800 times of 50% dichlorvos.
The above chemicals can also treat other pests at the same time. In addition, we should always check the orchard and kill the longicorn at any time.