First, sowing and seedling raising of leeks
Leek has strong adaptability to soil, but the most suitable soil for leek growth is neutral or slightly alkaline sandy soil with convenient drainage irrigation, soil organic matter content above 2% and pH value of 7~8.
1. Soil preparation, fertilization, border cultivation in the nursery.
Select the nursery land where onion and garlic crops have not been planted in recent 2-3 years, and apply 2000-3000 kg of decomposed organic fertilizer and 25 kg of ternary compound fertilizer with the ratio of nitrogen, phosphorus and potassium of about 16-8- 18 per mu in combination with soil preparation, then dig deeply, level and rake finely after deep digging, and make1.
2. Sowing time and method
Leek can be sown from the thawing of soil in spring to the autumnal equinox, but most areas mainly sow in spring, and the sowing time is usually from late March to early May, so all localities can flexibly choose the sowing time according to local actual climate conditions.
(1) soaking seeds in warm soup to accelerate germination
Before sowing, the selected Chinese chive seeds are soaked in constant temperature water at 55℃ for about 20 minutes, then soaked in warm water at 25℃~30℃ for 12 hour, then wrapped in cotton gauze after taking out, and treated at constant temperature of 15℃~20℃ to accelerate germination, and sowing can be carried out when more than half of the seeds are white.
(2) sowing
Before sowing, water should be poured into the flat border prepared during soil preparation, and after water infiltration, a layer of fine soil of about 1 cm should be covered, and then seeds should be sown in the border for 2-3 times, with a general sowing amount of 4-5 kg per mu. After sowing, a layer of fine soil of about 1 cm should be covered and plastic film should be covered for heat preservation and moisture conservation, which is conditional.
3. Management of leek seedling stage
After the leek seeds germinate and break the ground, the plastic film should be removed in time to prevent the seedlings from burning due to excessive soil temperature. Before the seedlings grow 1 true leaf to 4 true leaves, because the root system of leek seedlings is thin and mostly distributed in the soil surface, water management becomes very critical, and it is generally required to water the border once every 5-6 days to ensure that the border surface is moist.
When the plant grows to about12cm, the root system of Chinese chives has been developed, so it is appropriate to control water and squat the seedlings to prevent the Chinese chives from lodging due to excessive growth. When the seedlings grow to about 15 cm, combined with watering, topdressing ternary compound fertilizer 10/0 kg with the ratio of nitrogen, phosphorus and potassium of about 16-8- 18 per mu to promote the growth of seedlings. When the plant height is about 20 cm and there are 5~8 leaves, the seedlings can be transplanted and planted.
Second, transplanting and planting leek seedlings
1. Soil preparation, fertilization and border cultivation
Before transplanting and planting, soil preparation and fertilization should be carried out first. Combined with soil preparation, 4,000-5,000 kilograms of decomposed organic fertilizer and 25 kilograms of ternary compound fertilizer with the ratio of nitrogen, phosphorus and potassium of about 16-8-28 should be applied per mu, and then a flat border of about 2 meters should be made.
2. Transplanting and planting
When sorting seedlings after seedling emergence, cut off the excessively long tip and fibrous root, and keep the tip length of10cm and the fibrous root length of 2-3cm, which can effectively prevent water evaporation and promote root development, and then dip the root with phoxim.
Trenching is carried out on the whole border, and the depth of trenching is about 10 cm, and transplanting and planting are carried out according to the row spacing of about 20 cm, the hole spacing of about 10~ 15 cm, and the planting of each hole is about 10~ 15 seedlings, and each planting
Third, field management measures after planting leek
1. Field management measures in the year after planting
After planting, Chinese chives enter the field management stage. When new leaves come out, slow seedling water should be poured in time and intertillage should be carried out, and the soil should be kept dry and wet. After the leek enters the rapid growth period, it is generally enough to apply fertilizer twice in combination with watering. Because leek is a leafy vegetable crop, many vegetable farmers like to apply only nitrogen fertilizer, which is an unreasonable fertilization method. In order to produce high-quality and high-yield leeks, balanced fertilization should be paid attention to, and fertilization should be carried out according to the fertilizer demand characteristics of leeks, and 20 kilograms of ternary compound fertilizer with the ratio of nitrogen, phosphorus and potassium of 16-8- 18 should be applied per mu each time.
Before the soil is frozen, the frozen water should be poured in time, and the fine soil and the decomposed organic fertilizer should be mixed evenly to cover the rows to ensure the leek plants to survive the winter smoothly, and the amount of organic fertilizer per mu is about 2 cubic meters.
2. Field management in the second year and after planting
Leek is a perennial vegetable crop, and corresponding management measures should be taken according to its growth characteristics in different seasons.
(1) spring management
Due to the drought and lack of rain in most areas of China in spring, green water should be watered in time according to soil moisture content, and green fertilizer should be applied in combination with watering. The ternary compound fertilizer with the ratio of nitrogen, phosphorus and potassium 16-8- 18/0 kg can be applied per mu.
From the practical management point of view, it is better to combine watering and fertilization for each leek 2~3 days after harvest, and 20 kg of ternary compound fertilizer with nitrogen fertilizer can be topdressing with water, and intertillage and weeding can be carried out in time after watering and fertilization.
(2) Summer management
Because there is more rain in summer, it is necessary to reduce the amount of watering according to the actual soil moisture, pay attention to drainage and clean up the yellow leaves and leek moss near the ground in time to reduce the consumption of nutrients.
(3) Autumn management
Autumn management of leeks is very important. Generally, leek grows in autumn and reaches its vigorous growth period. At this time, it is necessary to strengthen the management of fertilizer and water. From late August, it should be watered once every 6 days or so, and at the same time, it is still 2~3 days after harvest. Combined with watering and fertilization, the amount of fertilization is the same as that of topdressing in spring.
(4) Winter management
After entering 1 1 month, the weather will gradually turn cold, which can make leek plants die naturally to ensure that nutrients flow back to the roots. Before entering the winter, it is necessary to pour frozen water in time, and spread decomposed organic fertilizer mixed with fine soil to keep warm.
3. Prevention and control of leek diseases and insect pests
The most harmful pests of leek are leek maggots, and the diseases such as gray mold and rust are the most frequent.
(1) Control of leek pests
Leek maggots are the most harmful pests in leek planting, so special attention should be paid to prevention and control.
Agricultural control: sugar, vinegar, liquor, water and 90% trichlorfon crystal can be prepared into trapping liquid according to the ratio of 3: 3:1:10: 0.6, and 1~3 places can be placed per mu, which can effectively trap and kill seed flies; Chemical control: phoxim EC, thiamethoxam SC, matrine and azadirachtin EC can be used for root irrigation 2-3 days after leek harvesting. At the peak of the damage, stir-fried wheat bran or bean cake can be mixed into trichlorfon to make poison bait, and the poison bait is put into the pit every 3~4 meters and covered with soil for trapping and killing. (2) Control of leek diseases
Botrytis cinerea: polyoxin or Trichoderma can be used for spray prevention, and procymidone and imidacloprid can be used for control at the initial stage of the disease; Rust: Rust can be controlled by triadimefon. Fourth, timely harvest
When the leek seedlings grow to 25~35 cm, they can be harvested. Due to the poor quality of leeks harvested in summer, most of them are harvested in spring and autumn, and it is best to harvest them in sunny early morning, and the cutting edge is about 2~4 cm from the ground.
In the process of planting leek, besides seedling management, it is important to ensure the smooth overwintering of leek seedlings and the management of water and fertilizer in the field, so vegetable farmers should pay special attention to it.