Detailed Explanation of Key Points for High-Yield Spring Potato Cultivation Techniques
The potato is an annual herbaceous plant in the Solanaceae family, genus Solanum, also known as di dan, yang yu, tu dou, etc. The earliest artificial cultivation sites of the potato can be traced back to approximately 8000 to 5000 BC in the southern region of Peru. The potato grows 15-80 cm tall, hairless or sparsely pubescent. The stem is divided into two parts: the aboveground stem and the underground stem. The potato is one of China's five major staple foods, with high nutritional value, strong adaptability, and high yield. It is the world's third most important food crop, after wheat and corn.
Growing conditions for potatoes
Potato planting site: The potato prefers cool conditions and is a crop that likes low temperatures. The formation and growth of its underground tubers require a loose, breathable, cool, and moist soil environment.
Temperature requirements for potatoes: The optimum temperature for tuber growth is 16°C~18°C. When the soil temperature is above 25°C, tuber growth stops. The optimum temperature for stem and leaf growth is 15°C~25°C, and growth stops above 39°C.
The potato was introduced to China only a little over 300 years ago. It is said to have been brought in by overseas Chinese from Southeast Asia. In the 21st century, China's potato planting area ranks second in the world. Potatoes have high yields, are rich in nutrients, and have strong adaptability to the environment. They are now found all over the world, and tropical and subtropical countries can even cultivate them in winter or in cool seasons and obtain relatively high yields.
Key points for high-yield spring potato cultivation
Every year in early April, potato seed pieces are planted in a shed. In early May, when the potato seedlings have grown to 2 cun in height, they are transplanted into the field. Early potatoes can be harvested half a month ahead of time at the end of June. The specific management techniques are as follows:
1. Cutting seed pieces and sprouting
Begin sprouting 20 days before sowing, around early March. When cutting potato seed pieces, each piece should have at least one eye. 10-15 pieces/jin is appropriate. After cutting, mix with dry plant ash or soak the seed pieces in a 1:200 dilution of carbendazim powder in water for sterilization and disinfection. After the seed pieces are dried, begin sprouting in a seedbed. There are two methods: one is to sprout with sand in a corner of a room at a room temperature above 15°C, with one layer of sand and one layer of seed pieces; the other is to dig a pit outdoors in a ventilated, sunny spot oriented east-west for sprouting, with a pit depth of about 25 cm, one layer of sand and one layer of seed pieces, preferably 3 layers, then cover with an arched film, and add straw curtains at night for insulation. During the sprouting period, these two methods require sprinkling water 1-2 times to prevent drying out. When the sprouts grow to 0.5-1.0 cm in length, begin sowing.
2. Land preparation and trenching
Before planting, check the soil moisture. If the moisture is poor, consider irrigating the trenches to build up moisture, preferably 7-10 days before planting. Potato planting generally uses double-trench planting. When opening trenches, a large row spacing of 50 cm and a small row spacing of 40 cm can be used.
3. Sowing and covering with film
The best period is from the Spring Equinox to Qingming. It should be especially noted here that virus-free potatoes can be sown earlier, with sowing completed before the Spring Equinox, and plant spacing can be controlled at 20 cm. Before sowing, first spray the trenches with phoxim at a 1:10000 dilution in water to prevent underground pests. Organic fertilizer can be spread directly into the trenches or applied during land preparation; chemical fertilizer can be mixed into the trenches or spread between the seed pieces (note that it must not come into direct contact with the seed pieces). When sowing, there are two methods for placing the seed pieces into the trenches: one is with the sprout facing down. Potatoes grown this way have long roots and strong seedlings, with fewer but larger potatoes, but the seedlings emerge 2-3 days later. The other method is with the sprout facing up. Potatoes grown this way have relatively shorter roots, with small but numerous potatoes, and the seedlings emerge 2-3 days earlier. After planting is completed, take soil from both sides within the large rows to cover the potato trenches and the spaces in the small rows, then level them. Cover tightly with microfilm and press it down firmly.
4. Ventilation after emergence and seedling-stage management
After Qingming, about 20 days after sowing, seedlings emerge from the soil. At this time, tear open the microfilm at the seedling positions for ventilation to prevent steaming the seedlings. When the seedlings grow to 10 cm tall, press the film around the seedlings firmly with soil to retain water and suppress weeds. Potatoes should not be watered in the early stage of growth; water only after flowers appear. If there is drought and no rain, water once every 10 days. Generally, 2-3 waterings are enough for the potatoes to mature. Stop watering 10 days before harvest. During the seedling stage, prevent pests such as aphids and thrips.
5. Rational fertilization
Potatoes respond well to farmyard manure, preferably 4000-5000 jin per 666.7 sq m, and when applying chemical fertilizer appropriately, nitrogen, phosphorus, and potassium should be used in combination. Potatoes have a high demand for potassium. The scientifically reasonable input ratio of nitrogen, phosphorus, and potassium is 1.85:1:2.1. Potatoes like to absorb ammonium nitrogen and absorb relatively large amounts of sulfur. According to experiments, for every additional 1 kg of potassium sulfate fertilizer applied, potato yield can increase by 100-150 kg.