The grapes to produce the Riesling Marlborough Greywacke were hand-picked at moderate ripeness levels to capture the exuberance and natural acidity of the variety, and were whole bunch pressed using a very low maceration press cycle. The resulting juice was cold-settled, then racked to fermentation vessels. Half of the juice was inoculated in a stainless steel tank using cultured yeast, while the other half was filled into old French oak barriques, where it was allowed to undergo spontaneous indigenous yeast fermentation. All of the wine was then transferred to a stainless steel tank where the fermentation was stopped, retaining 19 g/l residual sugar. The blended wine was filled into old barrels, where it remained on yeast lees for a further five months.
The fruit for this wine was grown at the organically-farmed Ashmore Vineyard in Fairhall, adjacent to the mouth of the Brancott Valley on gravelly clay-loam soils, conditions more typical of the Southern Valleys than the Wairau plains. The 23-year-old vines are trained on a two cane VSP (Vertical Shoot Positioning) trellis with careful shoot and bunch thinning carried out.
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’.