What is the difference between potassium nitrate, potassium sulfate and potassium dihydrogen phosphate?

According to the introduction of general manager Liu of Tongli Chemical Co., Ltd., the fertilizers as excellent potassium sources are potassium nitrate, potassium sulfate, potassium dihydrogen phosphate and potassium chloride, with the following differences:

It contains 13.5% nitrate nitrogen and 46% potassium. It is a chemical neutral and physiological neutral fertilizer with good water solubility. Long-term application will not lead to soil acidification. It can be applied to the period from the expansion of young fruits to the initial stage of coloring of vegetables and fruit trees and can promote the expansion of pulp cells. Because it contains nitrate nitrogen, it is not recommended to use in the later stage of coloring, which is easy to cause green.

Potassium dihydrogen phosphate

It contains 52% phosphorus and 34% potassium. It is a chemical neutral and physiological neutral fertilizer with good water solubility. Generally, before and after flowering, it can be used to promote root germination and flower bud differentiation and provide energy for flowering and fruit setting.

The application during the coloring period can promote the powder coloring and increase the sweetness of the fruit; the application after the fruit picking can promote the branches to mature and improve the degree of the fruit lignification.

Many people ask potassium nitrate and potassium dihydrogen phosphate, which is better? In fact, there is no better way to say it. The key is how to use it. The two of them contain different elements.

Potassium nitrate is a binary compound fertilizer of nitrogen and potassium, and potassium dihydrogen phosphate is a binary compound fertilizer of phosphorus and potassium. Therefore, different products should be adopted according to different periods. Nitrate nitrogen in potassium nitrate is easily lost by rain, so it is generally not recommended to use in paddy field.

As for potassium nitrate and potassium dihydrogen phosphate, it can be understood that when the amount of nitrogen used for crop growth is large, potassium nitrate is used; when the amount of phosphorus needed for crop growth is large, potassium dihydrogen phosphate is used. Potassium nitrate was used for expansion and potassium dihydrogen phosphate was used for coloring. Potassium nitrate was used in normal growth period and potassium dihydrogen phosphate was used in flowering and fruiting period.

Strictly speaking, these two products cannot be regarded as pure potash fertilizer. Even potassium dihydrogen phosphate is classified as phosphate fertilizer in many classifications.

These two kinds of fertilizers are quick acting fertilizers, and the market price is higher than that of ordinary potash. Therefore, it is not recommended to use them as base fertilizers, especially potassium nitrate. They are used for topdressing or extra root fertilization. If there are conditions, you can use the two together, it will be better.

Many high-end water-soluble fertilizer liquid potassium phosphite raw materials will use these two things. The most important point is the quality of these two products made in China. As long as they are regular manufacturers, they can still do it. There is no need to import them.

Potassium sulphate

The potassium content is 54% in theory, generally 50%, which is chemical neutral and physiological acid fertilizer with good water solubility. However, long-term use will aggravate soil acidification, which is suitable for the later stage of fruit coloring to the mature stage of fruit, promote the pink coloring on fruit and increase the sweetness of fruit.

It is said that manganese poisoning in many fruit tree areas is caused by soil acidification, and one of the direct causes of soil acidification is the perennial use of potassium sulfate.