Biochar from vineyard waste improves soil carbon and water retention in New Zealand wine industry trials

New Zealand researchers at Lincoln University are testing biochar and compost made from grape marc, vineyard prunings, and forestry waste as soil amendments for vineyards. Field trials show biochar improves aggregate stability, water holding capacity, and nutrient uptake in grapevines, especially on free draining soils. The carbon in biochar remains stable for decades, unlike compost which breaks down quickly. The research also tests using biochar to establish native plants on vineyard margins, supporting pollinator habitats and carbon sequestration. For growers, replanting and new block establishment are the most practical entry points for biochar application. The work is funded by the Bioresource Processing Alliance and Brian Mason Trust, with partners including Green Circle NZ and Bragato Research Institute.