How to cultivate pollution-free carrots
I. Cultivation season and variety selection Most of China's carrot cultivation is in summer and autumn, and timely sowing is an important condition for obtaining high yield and high quality. The northeast region can be planted from the end of June to the end of July .
The varieties selected are different for different sowing times. Selection in the summer and autumn sowing can be based on the following principles:
　　 1. Choose a variety that has been cultivated in the north and has been successfully obtained or cultivated in a large area.
　　 2. Choose popular, easy-to-sell varieties on the market.
　　 3. Choose varieties with strong adaptability and moderate growth period.
　　 4. Choose varieties with good quality, high nutrient content and suitable processing.
Second, soil selection and soil fertilization carrots have higher requirements on soil. It is better to choose sandy loam or loam with good plough layer, loose soil and good drainage. Generally, it is scallions, Chinese cabbage, and food crops.
The cultivation method is generally ridge cultivation. Before the preparation of the land, it is necessary to first plough the cockroach and then apply the base fertilizer. Generally, 3000 to 4000 kilograms of fermented organic fertilizer is applied per 666.7 square meters , some grass ash or biological potassium fertilizer is 1 to 2 kilograms, and it is best to incorporate 30% in organic fertilizer. Chicken dung. Finally, deep ridges. If the fertilizer is insufficient, it can be applied as a broken ridge, and the ridge width is 65 to 70 cm.
3. Management after sowing and sowing In the north, most of the stalking methods are used for stalking, and the ridges are 20 to 25 cm wide and 2 to 3 cm deep, and the seeds are evenly scattered in the ditch, generally 666.7 square meters. The amount of rice used is 300 grams. In order to ensure even seeding, the appropriate amount of fine sand can be mixed into the seed, and the soil is covered with 1 to 2 cm after sowing , and then pressed and watered. In order to maintain the moisture in the soil and prevent the sun from being exposed to high temperatures, some wheat straw or straw can be covered on the ridge after sowing, and the grass is gradually removed after emergence.
The carrot seedling period is long, and it is in the hot and rainy season. All kinds of weeds grow very fast, and herbicides can be sprayed after sowing to prevent weed growth. Using 33% "Pendimethalin" EC per 666.7 square meters with 150 ml of water was added 75 kg Qimian spraying, with good results.
Before the seedlings, the seedlings should be carried out twice. The first seedlings should be carried out in the seedlings with 2 to 3 leaves. The seedlings with abnormal growth, weakness and sowing are removed, and the seedlings are 3 cm apart ; the second seedlings are in the seedlings 3 ~ When 4 leaves were used, the seedlings were 6 cm apart . Combine cultivating loose soil with each seedling. Weeding is still required after the first seedling, and can be carried out using herbicides in the same manner as after sowing.
IV. Irrigation and Fertilization Carrots have strong drought tolerance, and the demand for fertilizers is less than other crops. However, in order to produce high-quality and high-yield products, it is necessary to strengthen fertilizer and water management.
During sowing to the time of emergence, if there is no rain, it should be continuously watered to keep the soil moist. After the seedlings, the water requirement of the seedlings is not large. It is not advisable to water more water, so that the soil sees dry and wet, so as to promote the roots and prevent the seedlings from growing. The seedling period is in the rainy season. After the heavy rain, it should be drained in time. After the seedlings are planted, water should be poured once and the seedlings should be cultivated. When the fleshy root begins to expand, the seedlings are finished. From the swelling of the fleshy roots to 15 days before the harvest , water should be watered in time to keep the soil moist to promote the expansion of the fleshy roots.
Carrot seedlings need less fertilizer, and the bottom fertilizer is generally not considered topdressing. If you need topdressing, you can apply the decomposed organic fertilizer after the second inter- emergence , and you can also apply urea, apply 10 kg per 666.7 square meters to promote Seedling growth. After the fleshy roots are swollen, the amount of fertilizer needs to be increased. With the heavy fertilization of water, potassium fertilizer should be added to the fertilized organic fertilizer, and 10 kg of potassium sulfate per 666.7 square meters or 20 kg per 666.7 square meters of compound fertilizer can be applied .
The last cultivating is carried out before the leaf clumps are closed, and the fine soil is transplanted to the root head to prevent the roots from being exposed and exposed to the ground, resulting in a green head and affecting the quality.
Fifth, harvesting and storage of carrots from sowing to harvest time, in accordance with a variety of growth vary, early maturing varieties 80 to 90 days, the late varieties 100 to 140 days. In general, the fleshy roots are fully inflated and can be harvested when they meet the requirements of the commodity. The harvest is too early, the fleshy roots are not fully expanded, the yield is low, and the quality is poor. After the harvest is too late, the easy wood is plugged and the quality is lowered.
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