Natural Mineral Soil Amendments in Organic Viticulture: Traditional Practices, Local Resources, and Ecological Perspectives

Natural mineral soil amendments are receiving renewed attention in organic and regenerative viticulture because they can connect traditional local resources with soil remediation, soil-life restoration and climate adaptation. This partly protocol-based scoping narrative review synthesises evidence on rock powders, zeolites, clays, carbonates, gypsum, perlite, vermiculite, alginite and humic mineral materials. The review evaluates their roles in nutrient buffering, pH and cation-exchange regulation, water retention, microbial habitat formation, heavy-metal immobilisation and carbon-stabilising soil structure. It argues that mineral amendments are most effective when used with organic matter, cover crops, reduced tillage and locally adapted vineyard-floor management, rather than as stand-alone substitutes for fertilisers. Comparative tables and decision matrices are provided to link amendment choice to soil pH, texture, salinity, contamination risk, climate stress and organic certification rules. The paper highlights Central European resources, especially volcanic and organic-mineral deposits, while placing them in a global viticultural and agroecological context. The main limitations are slow and site-dependent nutrient release, potential contamination, over-mineralisation, extraction and transport impacts, cost, and uneven field evidence in vineyards. Future research should prioritise long-term replicated vineyard trials, microbial and rhizosphere indicators, life-cycle assessment and practical guidance for certified organic farms.