Greywacke’s signature ‘Wild Sauvignon’ is arguably Kevin Judd’s flagship white wine. This alternative New Zealand Sauvignon Blanc style is fermented in old oak barrels using indigenous yeast. This use of indigenous yeast results in a lengthy fermentation process that can last almost a year after harvest. Yet it is a process that rewards patience, resulting in a textured white of considerable depth and opulence, with a lingering savoury finish of tarragon and lightly smoked tea. Greywacke was created in 2009 by Kevin Judd, an early pioneer in Marlborough winemaking whose ground-breaking wines helped put this small New Zealand region on the world wine map. The name ‘Greywacke’ was adopted by Kevin for his first Marlborough vineyard in Rapaura, nodding to the prevalence of rounded greywacke river stones in the vineyard’s soils. ‘Greywacke’ is a sedimentary rock widely found in Marlborough, consisting of hard grey sandstone and darker mudstone layers.