Four Key Points for High-Yield Cultivation of Spring Potatoes

Last October, many people in this village sowed potatoes, but a frost hit and they were all frozen to death. I sowed potatoes twice myself, at the end of January and in February this year; although they were not frozen to death, they only grew foliage and produced few and small tubers, and many had their centers hollowed out by termites. In addition, he used continuous cropping. The reader asks when it is more suitable to sow potatoes, and how to prevent frost damage and termites.

For spring potatoes to be high-yielding, the main attention should be paid to the following four aspects:

Pay attention to timely sowing. If spring potatoes are sown too early, the seedlings are prone to frost damage and death after emergence. Potatoes can grow well only under cool climate conditions, especially during the tuber-setting stage; the organic nutrients in the leaves can be transported to the tubers only when the nighttime temperature is low. If sowing is too late, the higher temperatures and greater rainfall during the tuber-setting stage are both unfavorable for the transport of nutrients from the stems and leaves to the tubers, resulting in excessive vegetative growth of the aboveground stems and leaves. This is one of the important reasons why spring potatoes only grow foliage and produce few and small tubers. The sowing time should be determined according to the local climate and the market conditions at the time of harvest. As far as climate is concerned, when sowing spring potatoes, the soil temperature at a depth of 10 cm should reach 6-7°C, and the tuber-setting stage should occur when the monthly average temperature is 15-20°C. As far as the market is concerned, from March to May, the earlier spring potatoes reach the market, the higher the price. Therefore, under the premise that climate and cultivation conditions permit, sowing can be appropriately early to strive for a better market price. In our province, spring potatoes can be sown from late December to early January; low-altitude hilly and flat land can be sown appropriately early, while higher-altitude mountainous areas should be sown appropriately late.

Pay attention to crop rotation. Potatoes are not tolerant of continuous cropping. In continuously cropped land, underground pests such as white grubs (scarab larvae) and mole crickets are rampant, and pathogens such as bacterial wilt can survive in the soil, with soil being one of the main routes of their spread. Therefore, the disease incidence in continuously cropped land is significantly higher than in rotated land. Potatoes are a crop with a relatively high potassium requirement, and continuously cropped land is severely deficient in potassium and other nutrient elements, which affects the expansion of potato tubers. Potatoes belong to the Solanaceae family, so they cannot be continuously cropped with other Solanaceae crops such as pepper, eggplant, tobacco, and tomato, nor can they be continuously cropped with crops such as Chinese cabbage and cabbage, because they share common-source diseases with potatoes. Potatoes are better rotated with crops such as rice, rapeseed, wheat, corn, and soybean, which helps reduce the occurrence of diseases and also helps reduce weed growth.

Pay attention to frost prevention. Spring potatoes are prone to attacks by late spring frosts. For example, the frosty weather that occurred in March this year caused most spring potatoes to suffer frost injury to varying degrees, especially in low-lying areas. Potatoes have a relatively strong regenerative capacity. After the aboveground parts are frozen to death or injured by frost, new shoots will emerge from the stem base or underground parts, but their growth and development are delayed, the growing season is also significantly shortened, and as the temperature rises markedly, especially when rainfall increases markedly, excessive vegetative growth is likely to occur. This is one of the important reasons why the spring potato seedlings this year looked good but the yield dropped significantly. To prevent frost damage, in addition to avoiding sowing too early, attention should also be paid not to plant potatoes in low-lying areas. In hilly areas, in zones above 200 m in altitude with a relative height difference of about 100 m, and on the mid-slopes of mountainous land, especially on the mid-slope zones of south-facing and southwest-facing slopes, there is an obvious temperature inversion during frosty weather, and the diurnal temperature difference is small. Potatoes planted in these places suffer lighter frost damage, and if these places can be utilized, the frost prevention effect is better. On frosty nights, covering the potato field with plastic film or rice straw gives a relatively good frost prevention effect. To reach the market early, potatoes sown in October-November are best covered with arched plastic film, which can prevent both freezing and frosty weather and help achieve market listing from late March to early April of the following year.

Pay attention to the control of termites and other underground pests. About 500 g per mu of 10% phorate can be mixed with dry fine loess (mix evenly) and broadcast in the sowing furrow in the evening. From April to May each year, black light traps can be used for trapping and killing. In April, look for termite-built tunnels in plots infested by termites. When termites are found, spray a small amount of mirex technical powder to make them carry the poison back to the nest and kill the other termites. After spraying mirex, cover the field with plastic film and press it down with clods of soil to prevent rain from washing it away and reducing its effectiveness.