Sodium nitrates are also referred to as chilates or Chilean nitrate. These fertilizers contain amounts of nitrogen of up to 16 percent. These fertilizers make nitrogen, the most important component in plant growth, immediately available to plants. Sodium nitrates are considered a valuable source of nitrogen and are commonly added to the soil as a top and side dressing, especially when fertilizing younger plants and garden vegetables. Sodium nitrate fertilizers are especially useful in acidic soil. A careless or excessive use of sodium nitrate can lead to deflocculation, a process of soil breakdown or dispersion.
Rock phosphate is an inorganic fertilizer type that provides phosphorus to the soil. When provided enough rainfall, rock phosphate fertilizers result in extended growing periods with enhanced crop growth. Rock phosphate is an ideal remedy for acidic soils, which are phosphorus-deficient. However, since rock phosphate is insoluble in water, it must be pulverized before it is added to the soil. Rock phosphate is the raw ingredient used in the manufacture of superphosphate or water-soluble phosphoric acid.
Sulphate of potash is the inorganic fertilizer which supplies the third-most needed nutrient, potassium, to the soil. Inorganic potassium fertilizers should only be used when there is an absolute potassium deficiency in the soil. Sulphate of potash is obtained by treating potassium chloride with magnesium sulphate. The resulting inorganic fertilizer is readily soluble in water and can be used in the soil at any time until sowing. Muriate of potash is another inorganic potassium fertilizer available in crystal form. However sulphate of potash is favored over muriate of potash by many gardeners.