Sweet potato 1 planting technology, soil preparation and fertilization: soil preparation should be carried out in sunny days, the soil should be broken and finely ground, and after leveling, fertilization strips should be applied at the bottom of the ridge, with the ridge spacing of 80 cm and the ridge height of about 20 cm. Special organic compound fertilizer can be used as fertilizer. When the planting area is large, it is required to determine soil nitrogen, phosphorus, potassium and organic matter, and the soil pH value should also be determined in the south. It is not recommended to use ordinary compound fertilizer.

2. Pruning and topping: For potato pieces with many branches and vigorous growth, you can cut off two or three branches with scissors to let nutrients flow back and the potato pieces get more nutrients. Topping can regulate nutrient transport and promote nutrient transport to roots. When the potato seedlings grow to 40 ~ 60 cm, the tender shoots should be removed, and when the branches grow excessively, the tender shoots should also be removed.

3. Top dressing in time

① Seedling-raising fertilizer: after transplanting 15 days or so, combined with the first intertillage, 750 ~ 1000 kg of rare human and animal manure or 2.5 kg of urea should be topdressing per mu.

(2) Fertilization of potato: topdressing at the branch potato stage, generally combined with the second intertillage within one month after transplanting, with nitrogen fertilizer as the main fertilizer and phosphorus and potassium fertilizer as the supplement.

(3) Combined fertilization: after the stems and leaves are closed, the root tuber grows rapidly, and topdressing is needed when cracks appear on the ground. Each mu of topdressing urea 1.5 kg, calcium superphosphate eluant 10 kg, and potassium sulfate 3 kg are added with water to make a nutrient solution, which should be watered along the joint in cloudy or sunny afternoon, and the topdressing should be uniform.

The growth period of sweet potato is 1, and the prophase: the prophase is about 60 ~ 70 days for spring potato and 40 days for summer potato. At this stage, the stems and leaves grow slowly and the roots develop rapidly, mainly in the period of long fiber roots.

2. Mid-term: from pot sealing to the peak of stem and leaf growth, it takes about 50 days for spring potato and 30 days for summer potato. At this stage, the root tuber expands slowly and the stem and leaf grow fast, which is a period dominated by stem and leaf growth.

3. Late stage: the late stage is from the beginning of stem and leaf decline to harvest, from late August to spring potato, and from early September to summer potato, which is the main period of root expansion.

Planting area of sweet potato

Sweet potato planting areas in China are mainly distributed in Beijing, Shanxi, Shandong, Henan, Tianjin, Hebei, Northeast China, Inner Mongolia, Yunnan, Sichuan, Hubei, Gansu, Anhui, Fujian, Shaanxi, Hunan, Guangdong, Jiangsu, Jiangxi and other places. The main producing areas are Sixian in Anhui (the hometown of sweet potato in China), Lulong in Hebei, Liancheng in Henan and Dengzhou.

References:

Cultivation Techniques of Sweet Potato (Convolvulaceae)-Baidu Encyclopedia