Not All Rock Dust is Alike: Why Basalt is a Soil Remineralization ‘Rock Star’


As the byproduct of violent volcanic activity, basalt is not an amendment that people associate with dependable crop production. Yet adding basalt to soil and potting mixes is a natural coming-together of geology and biology. It’s Mother Earths own form of soil remineralization. Results include stronger root systems, healthier plants and increased yields.

Here’s what else you need to know about the benefits of basalt as a remineralizing soil booster:

  • Created through the cooling and solidification of magma and lava, basalt is the rock material that makes up most of the soils around the world. Compared to rocks which are high in quartz, basalt weathers relatively quickly which means that it begins to release nutrients to plants as soon as the roots make contact.
  • Basalt is rich in essential micronutrients like calcium, iron, magnesium and manganese. It also contains soluble silicon which contributes to the strength of cell walls and makes crops more resistant to pests and disease. Silicon also strengthens stems, helping plants stand tall and capture more light to maximize photosynthesis.
  • Basalt continues to deliver a steady flow of nutrients over time, even as it decomposes. The slow-release benefits of crushed volcanic basalt make it an effective way to minimize deficiencies, particularly with fast-growing crops that experience periods of rapid nutrient uptake.
  • Using basalt as a soil amendment is not new. In the 1930s researchers in Europe used finely ground basalt to treat and improve the productivity of degraded forest lands. One of the most comprehensive studies of the benefits of basalt came from D. Hotman de Villiers who conducted a series of long-term field trials on highly degraded soil that led to increased sugarcane yields on the island of Mauritius.

Healthy soil comes from a marvelously complex interaction between biology (soil microorganisms and plant material) and geology (decomposing rock material).  By adding volcanic basalt to our lawns and gardens, we are mimicking the Earth’s own method for producing healthy soil which in turn leads to healthier plants, healthier people—and a healthier planet.

About Cascade Minerals Remineralizing Soil Booster

Made of 100% finely milled volcanic basalt from Central Oregon, Cascade Minerals is an all-natural soil amendment that is listed by the Organic Materials Review Institute (OMRI) for use in organic production.