When is the best time for sweet potato topdressing?

When is the best time for sweet potato topdressing? Please give guidance from late August to early October, which is the root expansion period of sweet potato tubers in spring and summer, which is the key period of yield formation and the period that needs the most fertilizer. First, hole topdressing method: with a piece of manure, 20-30 cm from the main root, drill a hole about 30 cm deep, put in an appropriate amount of three-element compound fertilizer, and seal it with wet soil. if you drill a hole on both sides of the ridge, the effect will be better. This method increases the yield by about 20% per mu. Second, crack fertilizer method: when cracks appear in the expanded ground of sweet potatoes, use 500 grams of potassium dihydrogen phosphate per mu, add 400 kilograms of water, or 2.5 kilograms of urea and 10 kilograms of calcium superphosphate, add 500 kilograms of water, and form fertilizer liquid to irrigate cracks, 0.7-1 kilograms per plant. Half a month later, 100 kg of grass ash per mu plus 500 kg of water (soaked for 4 hours), the filtrate was sewn and sealed, and the yield was increased by more than 300 kg per mu. Third, foliar topdressing method: foliar spraying 0.3% potassium dihydrogen phosphate (or 2.5% potassium sulfate, 10% herbal ash, 2% sulfuric acid press, 0.3% superphosphate, 0.3% a urea) aqueous solution, sprayed once a week, this method increases the yield by 18% per mu. Click to get more sweet potato planting techniques click to get more vegetable planting techniques