Sweet potato, also known as the yam or sweet potato, is a highly productive crop with strong regenerative abilities and a high tolerance for poor soil conditions. It is particularly rich in potassium, which plays a crucial role in its growth and development. Among the three major nutrients—nitrogen, phosphorus, and potassium—potassium is required in the largest quantity, followed by nitrogen and phosphorus. The ideal nutrient ratio in the roots is 2:1:3 (N:P:K). This is because potassium helps extend the life of leaves, enhances photosynthesis, activates amylase, and speeds up starch synthesis and transport. Additionally, it strengthens the activity of the root formation layer, promoting the development and expansion of tuberous roots.
A deficiency in potassium can lead to several issues. In the early stages of growth, plants may show shortened internodes, smaller leaves, and shorter petioles. Later on, older leaves and veins may lose their green color, leading to severe necrosis, which significantly affects yield. Therefore, proper application of potash fertilizer is essential for achieving high and stable yields in sweet potato cultivation. There are several effective methods for applying potassium:
First, applying potash as a base fertilizer is fundamental for high yields. Organic manure should be the main component of the base fertilizer. For sandy soils, which have poor water and nutrient retention, semi-mature organic fertilizers are recommended. Clay soils, on the other hand, benefit from well-rotted organic matter. A typical application rate is 150 kg of potash or 3,500–5,000 kg of high-potassium farmyard manure per acre. Wood ash can also be used, but it should not be mixed with ammonium-based nitrogen or human waste to prevent nitrogen loss through volatilization. Moreover, sweet potato is sensitive to chloride, so potassium chloride should be avoided.
Second, soaking the vines before planting can improve survival rates and encourage early root development. The method involves mixing 0.5 kg of potassium sulfate with 25 liters of water to create a 2% solution. Cut sweet potato seedlings are then soaked in this solution for one hour, ensuring that the cut ends remain submerged. Afterward, they are removed, dried, and planted.
Third, top-dressing is an important step around 40 days after planting. Apply 10 kg of potassium sulfate per 667 square meters by digging small holes 7–10 cm deep at the base of the plants, covering them with soil afterward to stimulate root growth. When the vines reach about 1 meter in height, apply 50 kg of wood ash per 667 square meters directly onto the leaves on a windless morning with no dew. This helps control vine elongation and promotes tuber expansion. During the tuber expansion phase, if the soil is moist or there is frequent rain, and the vines begin to yellow, additional ash can be applied.
Fourth, foliar spraying during the late growth stage can significantly boost yield. About 40–50 days before harvest, spray a 1% potassium sulfate solution, 0.2% potassium dihydrogen phosphate solution, or a 5% wood ash leaching solution (made by soaking 5 kg of ash in 100 liters of water for 24 hours and filtering) onto the leaves. Apply this every 7 days, for a total of 2–3 times, using 75–100 liters of solution per 667 square meters. Spraying is best done in the evening to allow better leaf absorption and improve fertilizer efficiency.
Corn Noodles,Gluten Noodles,Corn Macaroni Pasta,Corn Flour
YANBIAN ALALI FOOD CO. LTD , https://www.alalinoodles.com