How to manage sweet potatoes in the mid-growth stage? Master these key points

Drought prevention and drainage: In most areas with high temperatures and abundant rain, the aboveground stems and leaves of sweet potatoes grow rapidly, and nutrients move upward rather than downward. At this time, attention should be paid to drainage, that is, promptly and quickly remove standing water from the field surface after rain to control excessive aboveground growth. If there is drought, watering is needed to prevent it, so that the tubers can rapidly expand in soil that is neither wet nor dry.

Lifting vines and breaking roots, but no vine turning: In hot and rainy seasons, when soil moisture is too high, some sweet potato varieties root too much, especially in fields with high fertilizer and water levels, where sweet potato white roots grow abundantly and deeply. Lifting the vines can control excessive stem and leaf growth, and at the same time allow the ridge soil to dry and improve soil permeability. However, during this period, the vines must not be turned, because turning the vines easily damages the stems and leaves, disrupts the even distribution of leaves, affects the photosynthetic efficiency of the leaves, and causes reduced yield.

Spraying paclobutrazol multiple times: For sweet potato fields with excessive growth, use 50-70 grams of 15% paclobutrazol per mu mixed with 50 kg of water and spray it. Generally, spraying 2-3 times gives a better effect.

Topdressing tuber-promoting fertilizer: In the mid-growth stage of sweet potatoes, pay attention to topdressing potassium fertilizer such as potassium sulfate and plant ash. This is because potassium fertilizer can not only prolong leaf age but also improve photosynthetic efficiency, promote the movement of photosynthetic substances, increase the potassium-to-nitrogen ratio, and promote rapid tuber expansion. Apply 10 kg of potassium sulfate per mu, and apply 100-150 kg of plant ash per mu.

Controlling leaf-eating pests: In recent years, sweet potato hornworms have occurred severely in some places. Attention should be paid to observation and timely control once they are found.