It's on the market now, from late September to October.

1. Planting

Choose the land with rich moisture or the place with good water resources.

1. Planting time: generally speaking, the spring and autumn rainy season is suitable. From the end of February to the end of April in spring; Autumn from mid-September to mid-October. Conditional, other seasons can also be planted, but it is not suitable for planting in winter low temperature and summer drought conditions.

2. Planting density: the row spacing of plants is 4× 4m or 4× 5m, generally about 4 plants are planted per mu, or 5-6 plants can be planted in short density.

3. Planting method: (1) Before planting, dig a pit 1 meter square, apply a large amount of organic fertilizer and a proper amount of phosphate fertilizer as base fertilizer, and return the soil to 2-3 cm above the ground. (2) When planting, gently place the seedlings in the hole, plant them with loose and broken fine soil, compact the fine mud around the root group by hand, and expose the joint to the ground. (3) After planting, arrange the tray 2 cm above the ground and fill it with root water.

Second, soil cultivation

1. Deep ploughing to expand holes and mature soil: deep ploughing to improve soil, mature soil must be expanded year by year from the establishment of the garden. Young trees can dig annular ditches around the planting holes and plough deeply in different years. Adult pomelo orchards can be deeply ploughed in furrows around the crown, with a depth and width of about .5-.7 meters. Organic fertilizers such as green manure and inorganic fertilizers can be buried in layers, and they can be deeply ploughed every other year, alternately or every year.

2. Plant green manure and cultivate the land: Planting green manure to cover the ground can prevent erosion, reduce soil temperature, increase air humidity and inhibit weeds in summer, and at the same time increase soil organic matter and improve soil fertility. If legumes and vegetables are intercropped, the early benefits can be increased, and the stalks and residual branches will be covered and turned into the soil to increase soil organic matter.

3. intertillage and soil cultivation: weeding is combined during intertillage, generally 3-4 times a year, that is, after fruit picking in winter, sowing and intercropping are combined once each. The depth of intertillage is 1-15 cm (combined with intercropping and sowing, it should be deepened appropriately), and the closer it is to the trunk, the shallower it is, so as not to damage the big roots, and the soil should be cultivated before the dry season comes or after fruit picking in winter. In the gentle slope area, the soil should be cultivated once every 3-4 years, and once every other year in places with large slope and serious erosion.

3. Fertilization

Young trees are small, and their roots are tender, so it is advisable to apply thin fertilizer frequently, which can be applied 5-6 times a year. Generally, fertilizer should be applied four times to the bearing trees, namely, fertilizer for returning the sun, fertilizer for accelerating germination, fertilizer for stabilizing fruits and fertilizer for strengthening fruits.

1. Returning fertilizer (base fertilizer): it should be applied before and after fruit picking, and its fertilization amount accounts for half of the annual fertilization amount. A large number of late-acting fertilizers such as green manure, compost, manure and cake fertilizer should be applied, in combination with quick-acting nitrogen fertilizer and phosphorus fertilizer.

2. Preflowering fertilizer: Generally, it is carried out in February-March. This time, the fertilizer should be mainly available nitrogen fertilizer, mainly using human and animal manure, and appropriately combining urea.

3. Fruit-stabilizing fertilizer: quick-acting nitrogen fertilizer and phosphorus fertilizer can be applied half a month before fruit dropping in June, and decomposed human and animal manure can be applied, and 1% calcium superphosphate leaching solution can be sprayed.

4. strong fruit fertilizer: applied in the middle and late June, with quick-acting nitrogen fertilizer and "Woye Package" phosphorus and potassium fertilizer.

iv. irrigation and drainage

pomelo trees are evergreen all year round, with large annual growth of branches and tips, long fruit-bearing period, large leaves and large fruits, and high requirements for water. Cultivation of pomelo trees must ensure their water requirements through irrigation, and irrigation should be based on the water needs of pomelo trees in each phenological period and the drought situation at that time. Generally speaking, the growth and development of Hejiang need a proper amount of water, especially in the spring bud germination, flowering period and fruit growth peak period. Hejiang has a spring drought and a summer drought, so irrigation must be carried out at this time. Pay attention to drainage in places with low terrain and high groundwater level or in rainy season. Before rainy season or rainstorm season, check the drainage system of pomelo garden at any time, and repair and dredge it in time to ensure smooth drainage.

V. Shaping and pruning

The pomelo tree is strong and tall. When it is young, under the condition of abundant fertilizer and water, the top has strong advantages, and the branches grow upright, which is easy to form an obvious trunk tree. Many new shoots are strong, and the branches droop after fruiting, which makes the tree form an umbrella shape, so the light is not easy to penetrate into the crown, and the fruiting mother branches of the pomelo tree are mostly in the crown.

According to the growth and fruiting characteristics of pomelo trees, it is appropriate to choose "lateral trunk shape" and natural "happy shape" in production, with the stem height of 4-6 cm and the interval between main branches of 3-4 cm, and 5-6 main branches should be cultivated by * *. When pruning pomelo trees, it should be "heavy on the top, light on the four sides, heavy on the periphery and light on the inside", that is, pruning is sparse around the crown, the top branches are pruned again, and the internal branches are pruned lightly, so that the internal light of the crown is good, and the fruits are many and the quality is good. Generally, the slender leafless branches on the 3-4-year-old side branches in the crown are excellent fruiting mother branches, which must be reserved. The lateral branches that are too long or disturb the tree shape around the crown and affect the balance of tree potential should be thinned and cut short to achieve the purpose of ventilation. The tree is strong and should be cut again, while the tree is weak and should be cut lightly.

VI. Prevention and control of pests and diseases

There are many pests and diseases that harm pomelo trees, such as mites, scales, leaf miner, anthracnose, etc. The prevention and control should be based on the occurrence characteristics of various pests and diseases and combined with spraying.

1. Spray the pesticide twice continuously from the end of February to the beginning of April before flowering, mainly to control mites, and at the same time, use pesticides: insecticide+acaricide+bactericide in combination with other pests.

2. During the young fruit period after flower withering, spraying chemicals twice continuously, mainly to control scale insects, and combining with other pests, using pesticides: insecticide+bactericide.

3. From mid-autumn to early September, the pesticide is sprayed continuously for 3-4 times, mainly to control leaf miner, and also to treat butterfly and anthracnose, using pesticides: insecticide+bactericide.

The middle of April and September to the first ten days of October is the second peak of mite harm, so we should spray chemicals for 1-2 times to kill mites and treat other pests and diseases at the same time, and use pesticides: insecticide+acaricide+sterilization.

5. Spray the mixture of sulfur and stone once in winter to clean up the garden. The insecticides can be used alternately with chlorpyrifos and trichlorfon, the fungicides can be any one of carbendazim and zineb, and the acaricide can be sprayed alternately with propargite and mirex. The spraying should be even and thoughtful.