The Latest Requirements of Purple Sweet Potato for Its Growing Environment

Purple sweet potato can be grown in most parts of the country, and is mainly best suited to black soil, sandy loam soil and yellow earth. At present it is mainly grown in the Guangdong and Guangxi regions in the south, the Hunan and Hubei regions in central China, the Yunnan, Guizhou and Sichuan regions in the southwest, as well as the Shandong and Shaanxi regions. So what exactly are the specific requirements of purple sweet potato for its growing environment? We still need to analyse this together.

1. Soil

It has some requirements for soil. Sandy land is the most suitable, and even gravelly land that is unsuitable for other plants is very suitable for purple sweet potato. Purple sweet potato likes dryness and does not like moisture, so other soils with good water retention or heavy clay soils are particularly unsuitable for planting. Fields that have previously grown rice are especially unsuitable. It is suitable for growing in yellow earth and black soil.

2. Water

It does not like water and prefers dryness. With too much water, the underground roots and tubers are prone to rotting or infection by pathogens, and the edible roots and tubers may end up holding too much water, being watery after cooking and having a poor taste. Moreover, purple sweet potato, which mainly absorbs through its fibrous roots, is afraid of waterlogging, which affects the root system's absorption capacity and prevents it from absorbing nutrients. Planting in land with a high water content will reduce the yield, and the nutrient content will also decrease.

3. Temperature

Generally, the temperature during seedling raising must reach 15 degrees and must not be lower than 12 degrees. Temperature affects sprouting, and mainly the sprouted branches are taken for planting. At planting time the temperature is around 20 degrees. Since it is planted by cuttings, the temperature must not be too high; too high a temperature makes it hard to survive, and the cuttings are prone to dying. In cool weather there is less evaporation and higher air humidity, so the cuttings recover quickly and root very quickly. A cool temperature must be maintained for at least two weeks. Therefore the planting time is very important. During the tuber expansion period, the temperature needs to be above 20 degrees, around 25 degrees.

4. Nutrition

The base fertiliser is about 1000 jin per mu, and sufficient base fertiliser must be applied. In the early stage, mainly compound fertiliser or farmyard manure is applied, a fertiliser with comprehensive nutrients. Nitrogen fertiliser must not be applied alone; applying too much nitrogen fertiliser makes the branches and leaves too luxuriant, which is detrimental to tuber expansion. If the coverage area is too large, the field is difficult to manage. When the tubers begin to expand, phosphorus and potassium fertilisers are used. During the whole expansion period, fertiliser is applied twice, using potassium sulphate, diammonium phosphate, plant ash, livestock manure and the like.

Although purple sweet potato has some requirements for its growing environment, basically most places have a suitable growing environment for it. There may also be growing environments that are not so comprehensive. In actual production, what matters more is whether it can actually be grown, and what is looked at is the real effect.