What are the storage methods for seed sweet potatoes around Cold Dew?
As the saying goes, “seed sweet potatoes are afraid of freeze damage”, so how to store seed sweet potatoes is a problem. So what are the storage methods for seed sweet potatoes around Cold Dew?
1. Choose a good plot for seed sweet potatoes
Seed sweet potatoes should be selected and kept from plots with high and dry terrain, loose soil, a deep plow layer, excellent drainage, and ridge cultivation. Because such plots have good soil conditions, the sweet potatoes grow vigorously, resist disease, and store well. Sweet potatoes used for seed should have short vines, concentrated tuber formation, and a tuber shape with the typical characteristics of the original variety. The skin color should be relatively deep, the surface smooth, and the water content not too high; the tuber weight should be between 150 grams and 200 grams. Such tubers sprout abundantly, evenly, and vigorously.
2. Select plants in the field and keep them for seed
Select in fields that are disease-free and relatively lightly mixed, usually when the plants are round and beginning to trail vines, visually select individual plants that have the characteristics of this variety, grow vigorously, and have no disease spots, insert markers, and dig them up together with the plants at harvest. Usually, according to the planting area, select and keep no fewer than 200 plants per mu.
3. Harvest at the proper time
Harvest in clear and warm weather before heavy frost, otherwise the disease resistance and storage ability of seed sweet potatoes will decrease. Sweet potato is a warm-loving crop. For sweet potatoes kept for storage as seed, it is best to harvest when the soil temperature at 5 cm is stable at 10 degrees. Especially in September and October, the temperature changes greatly. In order to prevent seed sweet potatoes from suffering freeze damage, it is necessary to dig and harvest at the proper time according to weather changes. When harvesting, dig deep, sort carefully, and place gently, avoiding and preventing cuts and throws. After loading into baskets for transport, it is necessary to load, transport, and place them gently. Store them directly in the cellar. Reduce opportunities for bruising the tubers as much as possible. It is best to harvest in the morning, sun them in the field for a while, and put them into the cellar that afternoon to prevent freeze damage.
4. Do a good job of safe storage
1. Seed sweet potatoes must be stored separately from sweet potatoes for eating and potatoes. This can not only prevent diseases of eating sweet potatoes and potatoes from infecting seed sweet potatoes, but also resolve the conflict in which seed sweet potatoes suffer freeze damage while meeting the temperature requirements of potatoes during storage, or potatoes suffer heat injury while meeting the temperature requirements of seed sweet potatoes.
2. The local environment for storing and keeping seed sweet potatoes should be clean and dry, so choose a high, wind-sheltered, sunny place to dig a sweet potato seed cellar. If using an old cellar, scrape off the old soil to expose new soil, or spray with concentrated limewater, or fumigate with sulfur, and use other methods to disinfect, so as to prevent disease after the seed sweet potatoes enter the cellar. The bottom of the cellar should be lined with a layer of dry sand, and dry grass should be placed around it to prevent the seed tubers from becoming damp.
3. Before entering the cellar, seed sweet potatoes must be strictly and carefully selected, because during storage, sweet potatoes often rot due to black spot disease and soft rot. Therefore, select and store seed tubers that are unbroken, not freeze-damaged, not rotted at the top, and not infected by diseases or insect pests. At the same time, the seed sweet potatoes are required to have proper color, moderate size, and the typical characteristics of the variety.
4. When first put into the cellar, the respiration of the seed tubers is very strong and releases a lot of heat. When the seed tubers are piled together, the heat dissipates very slowly. The cellar door can be opened for proper ventilation. When the cellar temperature drops to around 12 degrees, close the cellar door. The cellar door temperature should be maintained between 1l and 15 degrees, and must not be lower than 1l degrees or higher than 18 degrees, to prevent freeze damage or sprouting. Diseased and rotting tubers should be picked out at any time.