When will sweet potatoes be planted in Northeast China? With high-yield planting techniques!

Sweet potato is a kind of nutritious and rich coarse grain food. it has a wide range of starch, which can be mixed with all kinds of meat, steamed cold skin with flour, or alone pancakes, mixing cold powder, etc. it is widely cultivated in the north and south of our country. So, when will sweet potatoes be planted in Northeast China? With high-yield planting techniques!

When will sweet potatoes be planted in Northeast China?

In Northeast China, when the average temperature is above 15 ℃, sweet potatoes with good seedlings can be cut and planted in the field, spring potatoes can be planted from late April to mid-May, and autumn planting should be carried out from the end of August to late September.

2. High-yielding planting techniques of sweet potato

1. Seed selection and nursery

The selection of seed potato requires typical characteristics of this variety, no diseases and insect pests, 100-250 grams of potato pieces. The planting density is about 3 cm apart, and the soil is covered after the seed potato is arranged, with a thickness of 2-3 cm, not more than 5 cm, so as not to affect seedling emergence. Remove the plastic film when 60% of the potatoes sprout. When the temperature is more than 20 ℃ on a sunny day, ventilation should be opened at both ends of the arch greenhouse film and the greenhouse film to prevent high temperature seedling burning and keep the bed temperature 25-30 ℃. The humidity of the bed soil shall prevail when the soil is dry and wet. When potato seedlings are 20-25 cm long and have 6-8 complete leaves, they can be cut and planted in the field.

2. Land selection and preparation

Sweet potato has developed root system and strong fertilizer absorption capacity, so it is appropriate to choose plots with deep soil layer, loose soil, good soil quality and strong irrigation and drainage capacity. Before planting, the land should be ploughed deeply, fertilizer can be applied first and then soil preparation, or hole or strip application can be applied after soil preparation. Soil preparation should be carried out on a sunny day, and the soil should be broken and fined. after leveling, fertilizer strips are applied at the bottom of the ridge, with a distance of 80 cm and a height of about 20 cm.

3. Planting

The seedlings can be cut and planted in the field when the average temperature is more than 15 ℃. Due to the low temperature in the early stage (from late April to mid-May), plastic film mulching can be used. When planting, the four nodes were inserted horizontally or obliquely into the soil, and the two leaves were exposed to the ground in case of drought, and the rest of the leaves were buried in the soil, so as to make the potato seedlings survive and spread evenly, increase the commodity rate and yield, and plant density 4000 plants / 667m ~ 2, plant spacing 20 cm.

4. Soil preparation and fertilization

Soil preparation should be carried out on a sunny day, and the soil should be broken and broken. After leveling, the fertilizer strip is applied at the bottom of the ridge, the distance between the ridge is 80 cm, and the ridge height is about 20 cm. Special organic compound fertilizer can be used for fertilizer. when the planting area is large, the soil n, p, k and organic matter should be determined, and the soil pH value should be determined in the south. The use of common compound fertilizer is not recommended.

5. Pruning and topping

For potato fields with more branches and more prosperous growth, two or three branches can be cut off with scissors, so that nutrients can be returned and potato pieces can get more nutrients. Topping can regulate the movement of nutrients and promote the transport of nutrients to the roots. When the potato seedlings grow to 40-60 cm, remove the tender tips, and when the branches grow too vigorously, they should also remove the tender tips.

6. Topdressing in time

About 15 days after planting, seedling raising fertilizer was topdressing rarefied human and animal manure with 750-1000kg or urea 2.5kg per 667m2 in combination with the first intertillage. The topdressing of tuber fertilizer in the branching and tuber stage is generally carried out within one month after planting combined with the second intertillage, mainly nitrogen fertilizer, combined with phosphorus and potassium fertilizer. After the stem and leaf were sealed, the root growth rate was faster, and topdressing fertilizer was applied when there were cracks in the ground. Every 667m2, urea 1.5kg, superphosphate leaching solution 10kg, potassium sulfate 3kg mixed with water 150-200kg were mixed into nutrient solution, which was irrigated along the seam in the afternoon of cloudy or sunny day.

7. Pest control

The main diseases are virus disease, black spot disease and purple feather disease. Control method: select disease-free seed potato, soak the seedlings with 2000 times solution for 5 minutes before planting, and the cuttings can be soaked with 1500 times solution of 25% carbendazim or 2000 times solution of 50% topiramate for 10 minutes.

The main pests are Spodoptera litura and sweet potato leaf beetle. Spodoptera litura can be sprayed with 10% 1000 times solution, 5% Yitaibao 800-1000 times solution or 48% Lesben 1000 times solution in late June. Sweet potato leaf beetle can be cut in potato seedlings for 30 days. Spray with 20% triazophos EC 600x or 2.5% enemy kill 4000 times.

Sweet potatoes in the harvest should be dug, light, light transport, light unloading, to prevent potato skin and pieces of damage. The storage temperature is 10-15 ℃ and the air relative humidity is 85% Mel 90 ℃. The storage place should be clean and hygienic, and do a good job of anti-rodent and anti-virus. At the same time, there should be heat preservation measures to prevent frostbite and extrusion, and pay attention to ventilation and heat dissipation.