What is gypsum, and why can it be used in place of lime?
Gypsum, also known as landplaster, is calcium sulfate. It is an economical source of calcium and sulfate but cannot be used as a liming material because it does not have the capability to neutralize soil acidity. In fact, applying gypsum to an acid soil (pH less than 5.5) can have adverse effects on certain crops by displacing soil aluminum, which is toxic to plant roots. Gypsum is frequently applied to crops to provide supplemental calcium. There is no substitute for lime in neutralizing soil acidity. Q: Why would a crop turn yellow after lime is applied? A: If plants appear chlorotic after a lime application, low manganese is usually the problem. Applying lime raises the soil pH and reduces the availability of manganese. In such cases, manganese should be applied to the soil. Soils with adequate manganese levels should not show symptoms following lime application. The yield increase attributable to lime should more than pay for applying manganese as wellnot to mention the residual be
Gypsum, also known as landplaster, is calcium sulfate. It is an economical source of calcium and sulfate but cannot be used as a liming material because it does not have the capability to neutralize soil acidity. In fact, applying gypsum to an acid soil (pH less than 5.5) can have adverse effects on certain crops by displacing soil aluminum, which is toxic to plant roots. Gypsum is frequently applied to crops to provide supplemental calcium. There is no substitute for lime in neutralizing soil acidity.
