One,
Leek and leek are the same plant. Leek grows in the open air and its leaves are green. Leek grows in shade and its leaves are yellow. The part of green onions buried in the soil is white, and the exposed part is green. Relevant scientific research has confirmed that there is no chlorophyll in yellow and white leaves.
2. 1, temperature: leek is a cold-resistant vegetable, which has a wide range of temperature adaptation and is not resistant to high temperature. The lowest germination temperature of leek is 2-3℃, the optimum germination temperature is 15-20℃, and the optimum growth temperature is 18-24℃. In the open field, when the temperature exceeds 24℃, the growth is slow, and when the temperature exceeds 35℃, the leaves are easy to wither and rot. Under the conditions of high temperature, strong light and drought, the cellulose in the leaves increases, the texture is rough and hard, the quality is poor, and it is even inedible. Under the condition of protected field, under the conditions of high temperature, high humidity and low light, the cellulose in leek leaves did not increase significantly, and the quality did not decrease significantly.
The bulbs and roots of Chinese chives have strong cold tolerance, and the bulbs and roots of Chinese chives entering dormancy can withstand the low temperature of -40 degrees. However, the harvested leeks are not cold-resistant because of nutrient loss. This requires that the protected leeks should be covered with heat preservation after cutting in late winter and early spring to prevent freezing to death, and the protective materials should not be removed too early, otherwise the weak leeks will easily freeze to death, and in serious cases, the whole field will be destroyed. So it is necessary to do this in production.
2, light: leek is a shade-tolerant vegetable, belonging to long-day plants. Low light tolerance, moderate light intensity and long light time make the leaves dark green, fat and strong, with high net photosynthetic rate, rich storage nutrition, high yield and good quality. When producing leek, special attention should be paid to adjusting the light intensity, completely shading, making the stem white, the leaves yellow and white, and the leaves appear beautiful pale yellow in the dark light. In production, soil cultivation and other methods are often used to cover yellow.
3. Moisture: Chinese chives like temperature, are afraid of waterlogging and drought, and are suitable for 80-95% soil humidity and lower 60-70% air humidity. Leek is very afraid of drought during germination, emergence and seedling stage, so the soil must be kept moist and the water content should not be lower than 80%. Without water, the germination rate is low, and the seedlings are easy to die of drought. For leeks that stop harvesting in spring, it is necessary to control water, hoe the soil in time and apply soil miscellaneous fertilizer to make them grow slowly, enrich the stems and leaves and strengthen the roots. If watering is not controlled, the stems and leaves will increase, tender and juicy, and prone to lodging and rot.
In summer, it is hot and rainy, the density of leek leaves is basic, the ventilation and light transmission are poor, and high temperature and high humidity can easily induce many diseases, leading to rotten roots and leaves, so attention should be paid to moisture prevention and drainage. Autumn is the best time for leeks to grow vigorously, because autumn is crisp and sunny. It is necessary to ensure adequate water supply, promote the healthy growth of plants and lay a solid nutritional foundation for high yield in winter and spring.
4. Soil and fertilizer: Chinese chives have wide adaptability to soil types. They grow best in high-quality soil and clayey soil with deep plough layer, fertile soil and strong water and fertility conservation. Sandy soil is easy to lose fertilizer and drought, leek grows weakly, the soil is sticky, easy to dry and crack, poor air permeability and easy to rot roots in summer. Leek has strong fertilizer tolerance, especially the ability to tolerate organic fertilizer. Leek mainly absorbs nitrogen fertilizer, supplemented by trace element fertilizers such as phosphorus and potassium. When transplanting leeks, base fertilizer should be applied again, otherwise the base fertilizer is insufficient and it is difficult to supplement after planting. It is best to use soil mixed fertilizer and organic fertilizer as base fertilizer. When applying chemical fertilizer, nitrogen, phosphorus and potassium should be applied together, and the ratio is 1: 0.83: 0.9 1. At the same time, trace element fertilizers such as zinc, iron and boron should be applied as appropriate. Topdressing is mainly nitrogen fertilizer, supplemented by potassium fertilizer. In autumn, leeks are flourishing, and after nutrient reflux accumulation, they are suitable for top dressing leaves.