Sweet potatoes , also known as yams, are a crop grown in many parts of China. They have good nutritional value and a wide range of uses. Spring is the planting season, so when should sweet potato seedlings be started? Let's find out below.
When should sweet potato seedlings be planted?
Sweet potato seedlings are generally started between the Jingzhe (Awakening of Insects) and Qingming Festival, which is from early February to late March. In southern regions where spring warms up quickly and temperatures are high, seedlings can be started in early February using plastic greenhouses or heated sheds. If seedlings are started in open fields using small arched sheds with plastic film, it will take until mid-March. In northern regions where temperatures are lower, seedlings in plastic greenhouses or heated sheds will need to be started in early March. Open-field seedlings will need to be started in April.
Methods of raising sweet potato seedlings
1. Seedbed preparation
Choose a plot of land that is sheltered from the wind and sunny, with high terrain, convenient irrigation and drainage, low groundwater level, and has not been planted with potato crops in the previous crop for seedling raising. The seedbed should have loose, fertile sandy loam soil. 500 kg of decomposed farmyard manure and 6 kg of ammonium sulfate can be applied per acre.
2. Selection of seed potatoes
Select seed potatoes with smooth skin, bright color, uniform size, no disease or injury, no cold damage, no water damage, and plenty of white sap as seed potatoes. The weight should be between 3 liang (150 grams) and 1 jin (500 grams).
3. Seed potato treatment
There are two methods for treating seed potatoes. One method is to soak them in warm water. Place the selected seed sweet potatoes in a bamboo basket, prepare a tank of warm water at 51-54℃, put the bamboo basket containing the sweet potatoes into the warm water, shake the basket to ensure the sweet potatoes are heated evenly, and take them out after soaking for 10 minutes. The other method is to soak them in a chemical solution. Alternatively, you can soak the seeds in a 200-fold dilution of 50% methyl thiophanate wettable powder for 10 minutes.
4. Seed potato planting
Soaked seed potatoes are then planted in the seedbed, a process also known as seed planting. Seed planting can be done diagonally, horizontally, or vertically. When planting, the heads and tails must be clearly distinguished, and the potatoes should not be planted upside down. Generally, the head of the potato has a darker skin color, more juice, and fewer fine roots. Because the tubers vary in size, they must be sorted and planted separately. The principle should be to plant larger tubers densely and smaller tubers sparsely, ensuring that the top and bottom are aligned, so that the soil covering the tubers is uniform, resulting in even and neat emergence and facilitating seedbed management.
