South Africa, but in practice problems with fruit set have limited its success. It is successfully grown in the Robertson district, and forms the main ingredient of the Van Loveren "River Red" blend. Spain Several DOs on the Islas Canarias include Ruby Cabernet in their authorized list of grape varieties including DO Lanzarote, Tacoronte-Acentejo, Valle de Güímar, and Valle de la Orotava. United States Ruby Cabernet is mostly planted in California, particularly in the San Joaquin Valley where it adds colour and backbone to bulk wines. Vineyards where farming techniques are employed to maximize quality however can produce wines with exceptional aroma, flavor, and mouth feel. Vine and Viticulture The vine is very drought resistant, and stands up well to high winds. Poor fruit set has been a problem in South Africa, and it is vulnerable to powdery mildew. In California's San Joaquin Valley, vineyards should limit irrigation, thin crop, and expose fruit to the sun to maximize wine quality. Vineyard ground The vineyards on which grapes for Ruby Cabernet are grown, are seat on vigorous grounds filled with deep clay loam. The canopies on these vineyards are usually quite open and not completely erected. The spacing below the vineyard row is normally of about seven to eight feet for optimal vertical shoot positioning. In case of vineyards which are quadrilateral and divided in a horizontal way, the space must be of about six to seven feet. References Red wine grape varieties