About Gypsum/Gypsum Mining

Gypsum consists of:

Two scrapers

Two scrapers mine the calcium-rich gypsum deposits left by ancient seas.

An operator

An operator monitors the gypsum mill.

Radial stacker

The mill grinds the gypsum to just the right consistency and distributes it in massive “hills”.
Inset: A close-up of the radial stacker depositing freshly-milled gypsum

Gypsum hills

The gypsum “hills” are even more impressive with a Holloway employee in the photo to show perspective.

Here are five key reasons why gypsum is useful in agriculture:

  1. Source of calcium and sulfur for plant nutrition. Plants are becoming more deficient for sulfur and the soil is not supplying enough of it. Gypsum is an excellent source of sulfur for plant nutrition and improving crop yield. Meanwhile, calcium is essential for most nutrients to be absorbed by plants’ roots. “Without adequate calcium, uptake mechanisms would fail,” Dick said. “Calcium helps stimulate root growth.”
  2. Improves acid soils and treats aluminum toxicity. One of gypsum’s main advantages is its ability to reduce aluminum toxicity, which often accompanies soil acidity, particularly in subsoils. Gypsum can improve some acid soils even beyond what lime can do for them, which makes it possible to have deeper rooting with resulting benefits to the crops. Surface-applied gypsum leaches down to the subsoil and results in increased root growth.
  3. Improves soil structure. Flocculation, or aggregation, is needed to give favorable soil structure for root growth and air and water movement. Clay dispersion and collapse of structure at the soil-air interface is a major contributor to crust formation. Gypsum has been used for many years to improve aggregation and inhibit or overcome dispersion in sodic soils.
  4. Soluble calcium enhances soil aggregation and porosity to improve water infiltration. It’s important to manage the calcium status of the soil, and it’s every bit as important as managing NPK.
  5. In soils having unfavorable calcium-magnesium rations, gypsum can create a more favorable ratio. Addition of soluble calcium can overcome the dispersion effects of magnesium or sodium ions and help promote flocculation and structure development in dispersed soils.

Gypsum Requirements During a Drought