Rocks can weather down from natural forces, or by activity of micro-organisms. By adding rock dust to organic matter, during the composting process, we mimic natural geological and biological process, the microbial activity makes available the nutrients in rock dust, which benefit plant growth.

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Earthworms eat soil mixed with organic matter, digest them through microbial action, and leave behind nutrient rich castings. Earthworms prefer soil with rock dust added.

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