Agricultural rock dust is a natural soil amendment made by finely crushing basalt rocks ,into a powder or grit.
It’s sometimes called rock powder, rock minerals, or mineral fines.
Here’s a breakdown:
Purpose
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Re-mineralization – It replenishes soils with essential trace minerals that may have been depleted through years of farming or erosion.
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Microbial support – Soil microbes use these minerals to break down organic matter and make nutrients available to plants.
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pH balancing – Certain rock dusts can help neutralize overly acidic soils.
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Improved plant health – Over time, plants grown in re-mineralized soil may show better resistance to pests and disease.
How It Works
Rock dust doesn’t feed plants directly in the way synthetic fertilizer does—it’s a slow-release mineral source.
Microbes, fungi, and natural weathering gradually make the minerals available, so benefits build up over seasons rather than instantly.
Application Tips
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Apply during soil preparation or at planting time.
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Work into the topsoil (5–10 cm deep) or spread on top as part of a mulch layer.
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Typical rates: 1–2 kg per m² for initial application, lighter top-ups annually.
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Combine with compost for faster microbial activity and better integration.
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