Greywacke was created in 2009 by Kevin Judd, chief winemaker at Cloudy Bay from its inception for 25 years and instrumental in the international recognition which Marlborough Sauvignon Blanc enjoys now. The name 'Greywacke' was adopted by Kevin for his first Marlborough vineyard located in Rapaura in recognition of the high prevalence of rounded greywacke river stones in the soils of the vineyard, a sedimentary rock which is widely found in
Marlborough. Kevin Judd is also New Zealand's finest wine photographer and has recently published a book 'The Landscape of New Zealand Wine'.

Fruit was sourced from various prime vineyard sites in Marlborough's Southern Valleys, the central Wairau Plains (specifically in Woodbourne, Renwick and Rapaura) and a spectacular river terrace site in the upper Awatere Valley. Soil types vary from the young alluvial soils of Rapaura, Renwick and
the upper Awatere, which contain high proportions of New Zealand's ubiquitous greywacke river stones, to the older and denser clay- loams of the Southern Valleys. The majority of the vineyards were trained using the divided Scott Henry canopy management system, with the balance on a vertical shoot positioning trellis.

Harvested largely by machine during cool (often cold) nights, the Sauvignon Blanc was picked into half-tonne bins, which were tipped directly into the tank press and lightly pressed. The resulting juice was cold-settled prior to fermentation, primarily using cultured yeast in stainless steel for cool, slow fermentation. A portion was allowed to undergo spontaneous indigenous yeast fermentation in old oak barrels. All individual vineyard batches were left on lees and kept separate until late July, when the blend was assembled.