Planting technique of purple yam

Purple yam is suitable for planting in fields with fertile soil, deep soil layer and convenient drainage and irrigation, and sprinkle rotten rapeseed cake fertilizer on the ground when ploughing the soil; select disease-free and damage-free seed potato, sow before and after Ching Ming Festival, and then cover with black plastic film to build a scaffold after emergence Urea and compound fertilizer were applied in the peak period of vines, urea and 0.3% potassium dihydrogen phosphate solution were sprayed in the later growth stage, and properly watered according to the soil conditions during the period, pay attention to the prevention and control of diseases and insect pests, and harvest was carried out at the end of October.

I. selection of land and cultivated land

Choose to plant in the fields with fertile soil, deep soil layer and convenient drainage and irrigation, generally take loam or sandy loam with good permeability, and then sunburn after deep ploughing, cultivated land to do border, border width is about 50cm, border height is about 30cm, ditch width is about 30cm, border surface should be fine and flat.

2. Seed potato treatment

Select the disease-free seed potato, remove the soil from the skin of the seed potato, disinfect the knife with 75% alcohol to avoid virus infection, and then cut into potato pieces of about 5cm, weighing 40-50g, coated with lime or lime, and sow the cut after drying.

Third, sow seeds at the right time

Before and after Ching Ming Festival, the planting method of single plant and single row can be adopted to sow seeds, the suitable plant spacing is about 30cm, the row spacing is about 80cm, and the sowing amount per mu is 2700-2800 plants per mu. In the middle of the ploughed border, a deep sowing ditch with 20cm is opened, the compound fertilizer is first applied into the ditch, then the broken soil with 2cm thickness is covered, and then the seed potato is covered with a small amount of fine soil, so that the sowing spacing and soil cover are uniform, and the seed amount is about 260jin per mu.

Fourth, cover the black film

After sowing, the border should be covered with a black plastic film with a width of 100cm. When covering the film, the film should be tightened, compacted around it, and suppressed with soil blocks every 2m on the film to avoid damage to the film by strong winds. When purple yam seedlings emerge, the seedlings should be broken in time to prevent the leaves from coming into contact with the plastic film and burn. Black film is generally used to cover the film, which has a better effect of warming, moisturizing, weeding and weeding than white plastic film.

Fifth, build a bracket

To build a support in time after emergence, so that purple yam climbing upward growth, usually can be inserted with a thin bamboo pole to build a herringbone frame, the frame height of 1.6-2.0 meters is appropriate, the support should be inserted firmly and tied tightly, so as not to be blown down by the wind, in order to avoid the purple yam vines intertwining with each other, you can also take advantage of the opportunity to evenly shelf the vines.

VI. Appropriate amount of fertilizer

1. Apply sufficient base fertilizer

Before ploughing the plot, you can evenly spread rotten rapeseed cake fertilizer on the ground, and then turn it deep to about 30cm to fully mix the soil and fertilizer, and then bury 45% potassium sulfate compound fertilizer in the sowing ditch according to the amount of 200jin per mu when sowing, the method is the same as sowing at the right time.

2. topdressing at the right time

In the full shelf period of vines, 20 jin of urea and 50-70 jin of high concentration compound fertilizer can be applied per mu, and urea and 0.3% potassium dihydrogen phosphate solution can be sprayed 2-3 times in the later growth stage, so that the leaves will not age.

7. Irrigation and drainage

In April-June, in case of continuous rainy and rainy weather, the stagnant water in the field should be discharged in time to avoid waterlogging, and in July-August, when there is a summer drought that lasts for more than 7 days, it is necessary to spray water in time to ensure that the soil is moist.

VIII. Control of diseases and insect pests

1. The main diseases and insect pests of purple yam are: grub, ground tiger, brown spot, anthrax, bacterial wilt, virus disease and so on.

2. Anthracnose and other diseases: in the early stage of the disease, 25% chlorpheniramine EC 75g can be sprayed with 100 jin of water per mu, and serious cases can be sprayed again every 7-10 days.

3. Pests and virus diseases: seed potatoes without virus should be selected for sowing. 5% carbaryl granules can be used in sowing or seedling stage or mixed with fine sand to control pests.

IX. Timely harvest

At the end of October, the purple yam plant will stop growing, and the tubers in the field are basically mature, which can be harvested in sunny days and should be harvested before frosting. Try not to damage the tuber epidermis and avoid tuber breaking.