How to grow sweet potatoes for higher yields? These four methods are very practical

For inverted planting, first cut off the top 2-3 nodes of the sweet potato vine, then cut it into sections of 4 nodes each, remove the petioles and leaves of the upper two nodes of each section, keep the petioles and leaves of the lower two nodes, and plant them upside down on the ridge, so that one petiole base is left exposed above the ridge surface, with a seedling spacing of generally about 15 cm. Although inverted-planted sweet potatoes grow more slowly than those planted upright, because the direction of the vascular tissue in the stem transporting water absorbed by the roots and organic matter is reversed, the transport speed slows down, and a large amount of organic nutrients accumulates at the roots, which is beneficial for tuber expansion and can increase yield by more than half.

Pinching the tips: When the main stem of the sweet potato grows to 40-50 cm, choose a sunny morning to pinch off the terminal bud; when the branches grow to 30-35 cm, continue to pinch off the terminal buds. This method can inhibit excessive vine growth, avoid nutrient consumption, promote tuber expansion, and can increase yield by 20-30%.

Crack fertilization: When sweet potatoes enter the tuber expansion stage, cracks will appear in the topsoil. At this time, use 750-1000 kg of clear water manure fertilizer per mu, mix with 500 g of potassium dihydrogen phosphate (or 5 kg of superphosphate and 50 kg of plant ash, soaked and filtered in water separately), mix into the manure fertilizer, and apply along the cracks in the morning or evening. After application, fill the cracks with soil, which can increase yield by 20-30%.

Spraying mepiquat chloride: When the sweet potato vines grow to 50-60 cm long, spray 10 mL of mepiquat chloride or 20-25 mL of growth promoter per mu, which can control the upper part and promote the lower part, prompting rapid tuber growth, and can increase yield by 15-20%.