Sweet potatoes are most afraid of three kinds of fertilizers

Sweet potato is one of the important economic crops in China. When planting sweet potatoes, we need to pay attention to the reasonable application of fertilizers to improve the yield and quality of sweet potatoes. However, when we plant sweet potatoes, we must pay attention to correct fertilization. If some fertilizers are used improperly, they will cause a decrease in sweet potato yields . Here we talk about the three types of fertilizers that sweet potatoes are most afraid of.

1. Sweet potatoes are most afraid of three kinds of fertilizers

1. Nitrogen fertilizer

Sweet potatoes require relatively little nitrogen during their growth, but nitrogen fertilizers contain a high content of nitrogen. If the nitrogen fertilizer content in the soil is too high, the sweet potatoes will grow stems and leaves excessively, while the growth of rhizomes will be inhibited, thus affecting yield and quality. In addition, nitrogen fertilizer will increase the nitrate content in sweet potato leaves, thus affecting the edible safety of sweet potatoes.

2. Potash Fertilizer

Sweet potatoes have a high demand for potassium, but if too much potassium fertilizer is used, the concentration of potassium ions in the soil will be too high, thus affecting the starch content and quality in the sweet potato rhizomes. In addition, excess potassium will affect the absorption and utilization of other elements in the soil, thereby adversely affecting the growth of sweet potatoes.

3. Acidic fertilizer

Sweet potatoes have high requirements for soil pH, and the suitable soil pH value is 5.5-6.5. Using too much acidic fertilizers, such as ammonium sulfate, magnesium sulfate, etc., will make the soil too acidic, which will not only affect the growth and development of sweet potatoes, but also inhibit the reproduction and activity of beneficial microorganisms in the soil, thereby damaging the soil ecological environment.

2. How to apply fertilizer correctly when growing sweet potatoes?

1. Base fertilizer

Before planting sweet potatoes, base fertilizer should be applied. Generally, compound fertilizer and organic fertilizer are used together. Compound fertilizer can provide various nutrients needed for sweet potato growth, and organic fertilizer can improve soil fertility. Fertilization should be carried out according to the growth needs of sweet potatoes and the nutrient conditions of the soil. Generally, 2000-3000 kg of organic fertilizer and 50-75 kg of compound fertilizer are used per mu.

2. Topdressing

Sweet potatoes require nutrients at different stages during their growth, and topdressing should be carried out according to the growth stage. In the early stages of sweet potato growth, fertilizers with high nitrogen content, such as urea, can be used to promote root development and rapid growth. In the middle and late stages of growth, the application amount of potassium fertilizer should be increased appropriately to promote the quality and sweetness of sweet potatoes. When applying fertilizer, attention should be paid to the time and amount of fertilization, and it should not be insufficient or excessive.

3. Foliar spraying

Foliar fertilization can improve the nutritional level of sweet potatoes and promote their development and growth. Generally, water-soluble fertilizers containing trace elements, nitrogen, phosphorus, potassium and other nutrients are used for foliar spraying. Do this every 10-15 days during the growth period of sweet potatoes. Be careful not to spray fertilizer on the leaves under high temperature or strong light.

4. Pay attention to fertilization techniques

When applying fertilizer, be sure to combine it with irrigation. Do not apply fertilizer on dry soil to avoid affecting the utilization and absorption of fertilizer. At the same time, attention should be paid to the time and amount of fertilization, and it should not be insufficient or excessive, so as not to affect the quality and yield of sweet potatoes.

In short, the application of fertilizer for sweet potato planting should be carried out according to the nutrient status of the soil and the growth stage of the sweet potato. Only by mastering the correct method of fertilizer application can we give full play to the role of fertilizer and improve the yield and quality of sweet potatoes.