What is 'gypsum'?

What is 'gypsum'?

Tracy DiSabato-Aust (Garden Designer and Author) gives expert video advice on: What are 'soil amendments'?; What is the difference between 'organic' and 'inorganic' soil amendments?; What is 'leaf humus'? and more...

Gypsum is calcium sulphate, and it's often sold to be used in clay soils. However, in most clay soils in the Midwest and the East, it does very little to improve the drainage or the soil structure. It can be used on soils that are high on salt content in the Western states, and it's effective as a soil amendment to improve the structure of the soil there.