Key Techniques and Management Measures for Winter Potato Cultivation
1. Pre-sowing preparation: In mid-February, prepare agricultural materials such as seed potatoes, pesticides, chemical fertilizers and agricultural film. Place the seed potatoes indoors at about 12°C to sprout.
2. Cut the seed potatoes: Make sure each seed potato piece has at least 1-2 eyes and weighs about 30 grams. Treat the cut seed potato pieces with a seed dressing. The formula for the medicinal powder is: add 250 grams of 70% thiophanate-methyl wettable powder to 50 kg of talcum powder.
3. Sow early at the right time: Generally sow from late January to early February, with a row spacing of 90 cm, a plant spacing of 12 cm, a sowing rate of 150 kg per mu, and a planting density of 5,000 to 5,200 plants per mu. Apply sufficient basal fertilizer per mu: 50 kg of potassium sulfate compound fertilizer, 20 kg of potassium sulfate, and 20 kg of urea. Cover with film promptly after sowing.
4. Field management:
(1) Open the film promptly. After potatoes are sown, seedlings generally begin to emerge in 25-30 days. At this time, assign dedicated personnel to inspect the field and promptly break open the agricultural film covering the seedlings when they emerge. If the film is not opened in time, the seedlings inside the film are very likely to be scalded by high temperatures. After about 80% of the seedlings in the whole field have emerged, remove all the agricultural film promptly.
(2) Cultivate and earth up. After the potatoes emerge and grow to about 8-10 cm, carry out the first cultivation. The most suitable hilling height is to leave 4-5 cm of the seedlings exposed. At the bud stage, carry out the second cultivation and hilling.
(3) Topdress and water. During the first cultivation, apply 20 kg of ammonium sulfate per mu as a top dressing. In addition, water promptly and properly for seedling preservation, at the bud stage, and during tuber expansion.
(4) Control pests and diseases promptly. In mid-to-late April, promptly control underground pests, and spray Shuangmeiyijing to prevent potato late blight. From late May to early June, promptly control aphids.