(1) Formula Fertilization Techniques for Leek Cultivation in Open Field
Before leek cultivation, root plants should be cultivated in the open field, which can be cultivated by direct seeding or seedling raising. At present, most areas in our country adopt the way of raising seedlings. Leek seedling occupies less land, is easy to manage, has less grass damage, strong root system and long life.
(1) Fertilize seedbed to cultivate strong seedlings: when using seedbed to raise seedlings, the seedbed should be selected in high dry land with dry water irrigation, drainage and leeward, and the soil where cotton, onion and garlic vegetables have not been planted for 3-4 years should be applied with high-quality decomposed organic fertilizer of 60,000-75,000 kg/ha, calcium superphosphate of 600 kg/ha and plant ash/kloc. After fertilization, turn it over 20 ~ 25 cm, carefully rake it flat and make it into a border. Before sowing, dry the seeds in sunny days 1 ~ 2 days to improve the germination rate and germination potential. Choose high-quality, high-yield, pest-resistant, stress-resistant, wide-adaptability and good-marketability leek varieties, such as 79 1, Pingjiu No.2, Shouguang Majie leek, Hanzhong Dongjiu leek, Beijing wire seedling, Hangzhou snowflake leek, Shanhaiguan wire seedling and so on. Water, topdressing, weeding and pest control should be done in time when seedlings emerge 10 ~ 15 days after sowing. It takes about 60 days to raise seedlings in seedbed, during which it is necessary to combine watering and topdressing for 2 ~ 3 times, and it is appropriate to use urea 150 ~ 300 kg/ha or diammonium phosphate 150 kg/ha each time. Seedlings with 7 ~ 9 leaves and plant height 18 ~ 20cm should be planted in time.
② Re-application of base fertilizer and timely planting: Although Chinese chives have strong adaptability to the soil, the production of pollution-free Chinese chives has strict requirements on the soil environment. You should choose a plot 0/000 ~ 2000m away from the pollution source/kloc-,where cotton and onion and garlic vegetables have not been planted for 3 ~ 4 years, and it is better to plant Chinese cabbage, Hana Haruna or the previous harvest Chinese cabbage. After the previous crop is harvested, it is necessary to clear the fields in time and plough and rake the fields. The plot for planting leeks in the open field should not be shorter than150m from east to west. Wind barriers should be set up in the northern region. After the wind deflector and the ridge are completed, it should be east-west. Apply 60,000-75,000 kg/ha of fully decomposed high-quality organic fertilizer, 300-450 kg/ha of diammonium phosphate and 1500 kg/ha of plant ash, spread evenly, turn over the ground, and rake the ridge surface after mixing the soil and fertilizer evenly. Generally, it is appropriate to use 3 million to 4.5 million plants/hectare.
③ Skillful topdressing: The overwintering ability and growth of leeks mainly depend on the amount of nutrients accumulated by plants before winter, and the accumulation of nutrients depends on the growth of leeks in autumn. Therefore, fertilizer and water management should be strengthened at seedling stage. Generally, it should be watered 1 time for 5 ~ 7 days, and the available nitrogen fertilizer should be topdressing for 2 ~ 3 times, with urea 150 ~ 225 kg/ha or diammonium phosphate 150 kg/ha each time, and finally diluted water with manure 15000 kg/ha should be watered/kloc-. Before overwintering, it is mainly to raise roots and trees, laying the foundation for the next spring harvest.
After warming up in the next spring, a layer of decomposed organic fertilizer of about 750 kg/ha can be spread on the border. More than two years old root leeks should also be covered with about 2 cm of soil. If possible, measures such as root planing, root pinching and soil cultivation can be taken to raise the ground temperature, kill leek maggots, loosen the soil, promote root growth and prevent lodging and root rot. If fertilization is applied at the end of winter, 22,500 kg/ha of decomposed soil miscellaneous fertilizer should be applied in spring, and it should be sprinkled on the border of 1 ~ 2 cm to facilitate the leek jumping. It is generally not suitable to water after fertilization in spring. If the weather is dry, water the seedlings after their height is 10 cm. Do not topdress with water, especially with quick-acting nitrogen fertilizer.
If there is more rain and snow in winter and the soil moisture is good, you can also start watering after the first harvest, loosen the soil in time and conserve water. When the new leaves grow 3-4 days after each harvest, appropriate topdressing, topdressing compound fertilizer 150 kg/ha or high-quality decomposed organic fertilizer 15000-22500 kg/ha.
When the temperature is high in summer, the fiber of leaf tissue increases, the texture is rough, and the growth is weakened, which shows dormancy. Generally, harvesting is no longer needed, so we should continue to strengthen root culture to lay a good foundation for autumn production. For perennial leeks, water control, fertilizer control, pest control and weeding should be the main measures.
Autumn has a cool climate and a large temperature difference between day and night, which is the most suitable season for leek growth and the best time to cultivate root plants. During this period, the physiological activity is the most vigorous, especially from beginning of autumn to the autumnal equinox, so it should be watered and fertilized again to promote its vigorous growth. Before and after beginning of autumn, 65,438+05,000 ~ 22,500 kg/ha of high-quality decomposed manure or 7,500 kg/ha of bean cake or 600 ~ 750 kg/ha of diammonium phosphate and 65,438+05 kg/ha of zinc sulfate were applied every time, and 65,438+0 times of water was applied every 5 ~ 7 days. When conditions permit, spray 1 times plant ash 1500 ~ 2250kg/ha respectively. Harvest from late August to late September 1 ~ 2 times. After entering June 5438+00, it is necessary to stop watering and topdressing, control the green growth of leeks by drought, and force nutrients to transfer to bulbs and roots to ensure safe wintering.
(2) Formula fertilization technology of leek in protected field.
Leek is planted under the protection of various forms of facilities. One is to cover the leeks after returning to the roots in the leek cultivation area, so that the root plants germinate and grow. The other is to re-store the root plants of Chinese chives in protective facilities and regenerate new plants by using the nutrients stored in the root plants, which is called Chinese chives storage. These two cultivation methods, such as cultivation, are called green leeks when the products are bright green under light conditions; The cultivation is yellow and white in color and fresh and tender in quality under the condition of no light. Taking leek as an example, the formula fertilization technology is as follows:
(1) Seeding and rooting: leeks that are continuously produced in autumn and winter need to be sown in the same year. In that year, the shed should be closed, 3-4 crops should be harvested continuously, the leek roots should be dug out, and other vegetables should be produced by stubble removal. Select excellent varieties suitable for continuous production in autumn and winter, such as Hangzhou Snow Leek, Sichuan Xipu Leek, Henan 29 1, Shandong Dugenhong, etc. Seeds need to be disinfected, germinated and sown to raise seedlings.
A. Direct-sowing bacon in the current year: soil preparation and sowing after thawing in spring, strengthening seedling management, and putting it into greenhouse film production after freezing in early winter of that year. Compared with two-year-old transplanting and rooting, this method has lower quality and yield, but it has the advantages of saving labor and land and good benefit.
The field with good drainage, fertile soil, loose texture and pH value of 5.6 ~ 6.5 should be selected for leek seedling, and continuous cropping with onion and garlic vegetables should be avoided. Soil that has not been planted with cotton for 3 ~ 4 years should be prepared before freezing or when it reaches 20 cm in the next spring. Apply 75,000 ~105,000 kg/ha of decomposed high-quality organic fertilizer, 750 kg/ha of calcium superphosphate or 0/5,000 ~ 22,500 kg/ha of cottonseed cake, and then add 2,250 kg/ha of calcium superphosphate and 0/5 kg/ha of zinc sulfate, deeply plough and harrow.
When the seedling height is 10 ~ 15 cm, the manure is diluted at 7500 kg/ha or 150 kg/ha with water topdressing. In the future, it is necessary to control water, cultivate soil and weed, squat seedlings and strengthen seedlings to prevent lodging and rotten seedlings.
After beginning of autumn, leek grows vigorously, so it is necessary to strengthen fertilizer and water management and pest control. Generally, water should be poured 1 time for 4 ~ 5 days, and combined with watering, 7,500kg/ha of decomposed organic fertilizer or 450 ~ 750kg/ha of diammonium phosphate should be topdressing, and plant ash1500 ~ 3,000kg/ha should be added. When conditions permit, cake fertilizer can be topdressing 3000 kg/ha. After 20 days, when the growth is weak, it can be chased 1 times.
The leeks produced in autumn and winter are sown and harvested in the same year. After harvesting 3 ~ 4 knives, plant leek roots. Therefore, no matter how early you sow, don't enter the early winter, and don't cut leeks in the open field before they hibernate. In summer and autumn, sometimes it grows too dense and prone to lodging, causing diseases. High shearing can be carried out at 8 ~ 10 cm above the leaves, and watering can be controlled by loosening the soil and ridging. When the local surface is about to freeze, it needs to be watered with frozen water, and it is best to combine watering with topdressing or compound fertilizer. Generally, 7500kg/ha of manure or 300kg/ha of NPK compound fertilizer is applied. Frozen water is the water source of the first leek, which is very important in protected field production.
Cover the greenhouse with plastic film before the frost appears. According to the growth and market situation of leek, cover it with plastic film after the first harvest or before the second harvest.
B. Transplanting to raise roots: In order to make leek plants grow regularly and improve yield and quality, it is best to transplant seedlings when conditions permit. It can be divided into sowing in the same year, transplanting and rooting in the same year and transplanting and rooting in the second year. It can be planted in spring or autumn.
Generally, every hectare of greenhouse needs about 4995 square meters of nursery land. When the surface freezes 20 cm in spring, make seedbeds with a width of 1 m and a length of 6 ~ 1m, apply 50 ~ 70 kg of decomposed farmyard manure to each bed, and plough deeply and rake flat. Open 4 ~ 5 shallow ditches for sowing, harrow, cover with plastic film to keep moisture and raise temperature, and promote early emergence. Mulching after emergence. When the seedling height is 10 ~ 15 cm, the manure and urine fertilizer should be watered to dilute 4500 ~ 7500 kg/ha or the ternary compound fertilizer of nitrogen, phosphorus and potassium 150 ~ 225 kg/ha.
After the early harvest in the shed, soil preparation and fertilization are carried out, and 75,000 ~1and 20,000 kg/ha of decomposed farmyard manure are spread, ploughed and raked, and ridged. In late June, the cultivated strong seedlings were planted in shallow ditches and watered with sufficient seedling-slowing water. After the new leaves grow green and the seedlings are delayed, topdressing with water will promote the growth of new roots and new leaves, topdressing with diammonium phosphate 150 ~ 300 kg/ha of water, timely intertillage and fertilize the soil, and then direct seeding will be used for root management.
② Fertilizer and water management after plastic film mulching: the temperature of leek in the early growth stage is low, the greenhouse is closed, and the water evaporation is less. Generally, plots that are fully watered with frozen water and chemical fertilizers are not watered before the first harvest. After the first harvest, loosen the soil immediately after each harvest. Water the new leaves after they grow, and topdressing diammonium phosphate with water is 450-750kg/ha. Topdressing and watering should be combined with soil cultivation. When the plant height is more than 10 cm, the second ridging cultivation is carried out when the plant height is about 20 cm, the compound fertilizer is scattered in the border, and the cultivated soil is poured along the border, and it is poured again after harvesting 1 ~ 2 days.
In the greenhouse where cucumber is cultivated in the next crop, cucumber should be planted on the ridge after the second crop is harvested, and the temperature and humidity should be adjusted and fertilizer and water management should be carried out according to the needs of cucumber. In the greenhouse where a single leek grows, the third and fourth leeks need to be exposed in the growing period, and the exposure time should be extended. The leek should be topdressing and watered at about 15cm, and the decomposed cake fertilizer should be applied at 4500kg/ha each time, or decomposed human excrement 15000kg/ha or 300kg/ha of ternary compound fertilizer of nitrogen, phosphorus and potassium. When conditions permit, topdressing 1 2,500kg/ha of plant ash can be applied separately. The fifth crop of leeks grows at the same time as the open leeks. In order to prevent yellowing, dry shoots and root rot caused by high temperature hazards, water should be used for fresh air and temperature control.
Because of the long growth period and many harvesting times of leek in protected field, fertilization and root raising are particularly important. Therefore, compared with the open field, the cultivation and fertilization in protected field increased by 65,438+00% ~ 20%, especially in late autumn and early spring. Organic fertilizers such as manure, horse manure, sheep manure and plant ash should be added to raise the ground temperature and put on the market early.
Mulched leek cultivation is prone to soil acid damage, so lime or plant ash should be applied before film mulching to adjust soil acidity, and a large number of decomposed organic fertilizers should be applied to improve soil buffering capacity. When there is acid damage after the film is buckled, the root can be irrigated with calcium nitrate fertilizer solution, and the effect is good.