Grapevine vigour is correlated with N-mineralization potential of soil from selected cool climate vineyards in Victoria, Australia

Excess vigour has been a problem on fertile soils under high rainfall in many cool climate regions of Australia. High and low vigour blocks were selected in vineyards of the cool climate regions of King Valley, Yarra Valley and Mornington Peninsula, Victoria. Laboratory incubations were carried out on soil samples to measure their N-mineralization potential (N₀). A strong relationship was observed between N₀ and soil total N concentration across all sites. Vine internode length measured between flowering and fruit set could be used as a index of vine vigour and was well correlated with N₀, but petiole N concentration was not a useful indicator of vigour at these sites. Sometimes high or low vigour may be due to other factors such soil water supply and soil depth, so that when interpreting a site’s potential for vigour all key soil and climatic variables should be considered.