Introduction

Erosion in farm lands have left behind poor soils, deficient in nutrients, and with reduced capacity to retain water. Compost is usually added to fix such soils. By adding rock dust to compost, we mimic natural processes, where organic acids from decomposing plant matter, make nutrients from rocks available to plants.

Composting

There are a couple of successful nutrient replenishment projects in Africa where locally available rock fertilizers were used on highly leached acid soils. [1]. This study emphasizes the potential of combining organic materials alongside rock fertilizers in soil fertility replenishment strategies.

Another study [2] found, for example, cocoa plants applied with basalt (5 or 10 t/ha ) had higher concentrations of K (1.4-fold), Mg (10- fold) and Ca (1.7-fold) than untreated controls; after 24 months, treated plants were 50% taller and 60% thicker- stemmed than controls.

It is better to sprinkle rock dust before starting the composting process. So when the compost gets ready, the nutrients in rock dust will be in a bio-available form, that can be easily absorbed by plants.

A Mexican company, Eco-Agro's [3]organic fertilizer is made up of worm leachate containing 5-6% mycorrhizae, a natural way of providing nitrogen to nutrient-poor soils, and 5-6% silicate rock dust with 52% silica and more than 70 trace elements. Rock dust is an essential ingredient in this compost; it not only accelerates the composting process inducing the growth of microorganisms but also provides depleted soils with a wide range of minerals and trace elements for healthy and nutrient-rich plant growth.

References

1. Anais da Academia Brasileira de Ciencias (2006) 78(4): 731-747 (Annals of the Brazilian Academy of Sciences) ISSN 0001-3765 www.scielo.br/aabc Farming with rocks and minerals: challenges and opportunities PETER VAN STRAATEN Department of Land Resource Science, University of Guelph, Guelph, ON, Canada N1G 2W1
2. Climate change mitigation: potential benefits and pitfalls of enhanced rock weathering in tropical agriculture David P. Edwards, Felix Lim1, Rachael H. James, Christopher R. Pearce, Julie Scholes, Robert P. Freckleton1and David J. Beerling
3. Rock Dust, Mother Earth’s Milk