Ammonium sulfate [(NH4) 2SO4], also known as ammonium sulfate, is the earliest nitrogen fertilizer (commonly known as fertilizer powder) produced and used domestically and internationally. It is suitable for general soil and crops, can promote vigorous growth of branches and leaves, improve fruit quality and yield, enhance crop resistance to disasters, and can be used as base fertilizer, topdressing, and seed fertilizer. It is usually regarded as a standard nitrogen fertilizer with a nitrogen content ranging from 20% to 21%.
Pure ammonium sulfate is a white crystalline substance, with a slight yellow or gray by-product. It has low moisture absorption and is not easy to clump, making it easier to store and more soluble in water. Ammonium sulfate is a physiological acidic quick acting nitrogen fertilizer that is generally suitable for crops such as wheat, corn, rice, cotton, sweet potatoes, hemp, fruit trees, vegetables, etc.
For soils, ammonium sulfate is most suitable for neutral and alkaline soils, but not for acidic soils. The application methods of ammonium sulfate mainly include the following:
1. As a base fertilizer. When ammonium sulfate is used as a base fertilizer, it should be deeply covered with soil to facilitate crop absorption.
2. Make top dressing. This is the most suitable application method.
Determine the topdressing amount of ammonium sulfate based on different soil types. For soil with poor water and fertilizer retention performance, it should be applied in stages, and the amount should not be too much each time; For soil with good water and fertilizer retention properties, the dosage can be appropriately increased each time. The amount of soil moisture also has a significant impact on fertilizer efficiency, especially in dry lands. When applying ammonium sulfate, it is necessary to pay attention to timely watering.
As for top dressing in paddy fields, it is necessary to drain and dry them first, and attention should be paid to applying them together with plowing and raking. In addition, there are also significant differences in the application of ammonium sulfate to different crops, such as when used for fruit trees, it can be applied in furrows, loops, or holes.
3. More suitable as seed fertilizer. Because ammonium sulfate has no adverse effect on seed germination.
Attention should be paid to the following issues when applying ammonium sulfate:
1. Ammonium sulfate fertilizer cannot be used in contact or mixed with other alkaline fertilizers or substances to prevent reduced fertilizer efficiency.
2. It is not advisable to apply ammonium sulfate on the same cultivated land for a long time, otherwise the soil will become acidic and harden. If it is necessary to apply it, an appropriate amount of lime or organic fertilizer can be applied together. But it must be noted that ammonium sulfate and lime cannot be mixed to prevent ammonium sulfate from decomposing and causing nitrogen loss. Generally, the combined application of the two should be separated by 3-5 days.
3. Ammonium sulfate is not suitable for application on acidic soil.
