Grape Guide
Ruby Cabernet
RedRuby Cabernet is a black-skinned crossing of Carignan and Cabernet Sauvignon, bred at the University of California, Davis, and released in 1948. Productive and heat-tolerant, it is grown mainly in hot irrigated regions such as California's San Joaquin Valley and South Africa, where it largely goes into blends and bulk wine.
Key characteristics
- A Carignan x Cabernet Sauvignon crossing made in 1936 by Harold P. Olmo
- Released to growers in 1948 at UC Davis
- Vigorous and very productive; yields must be controlled
- Late budding, mid to late ripening
- Very resistant to botrytis; moderately susceptible to powdery mildew
Typical flavors
Major regions
California (San Joaquin Valley) · South Africa (Robertson, Olifants River) · Australia (Riverland, Riverina, Murray Darling) · Texas (High Plains) · Brazil · Israel
Also known as
California 234 F 2 · Cabernet Ruby · Roubi Cabernet
Ruby Cabernet gives deeply coloured, medium-bodied reds with sweet red-fruit flavours and, when yields are held down, an occasional darker Cabernet-like tone. It was designed to carry Cabernet Sauvignon character into regions too hot for its parent, and it has done that job best as a volume and blending grape rather than a prestige one.
Varietal bottlings exist in California, South Africa, Australia, Texas, Brazil and Israel, but most of the crop goes into value blends, where it adds colour and softness. Californian plantings peaked in the 1960s and have shrunk since. The style is rustic and fruit-driven, so the best results come from controlled crops, sensible siting and, in warm regions, higher or cooler vineyards. Hectarage is now concentrated in a few hot, irrigated regions that supply bulk and supermarket wine.
The University of California, Davis was where Harold P. Olmo made Ruby Cabernet, in 1936, by pairing Cabernet Sauvignon with Carignan (known as Carignane in California and Mazuelo in Spain). It is the oldest of the wine-grape crosses that Olmo produced. He wanted a variety that would combine the flavour of Cabernet Sauvignon with the heat tolerance and generous yields of Carignan, so that growers in California's hot interior could turn out better inexpensive red wine.
The cross was released to growers in 1948. Its breeding code, California 234 F 2, survives as a synonym alongside Cabernet Ruby and Roubi Cabernet. The thinking mirrored that of Pinotage, the South African cross of Pinot Noir and Cinsaut made about a decade earlier: pair a prestigious parent with a hardy, high-yielding one and aim at warm-climate vineyards.
In the mid twentieth century it spread to other warm regions, mainly South Africa and Australia and, in smaller amounts, Israel, Brazil and Uruguay. Its peak of popularity in California came in the 1960s. Ruby Cabernet later served as a parent as well, most notably of Caberinta, an Argentine hybrid bred at INTA.
On deep, fertile soils of sandy loam or clay loam, Ruby Cabernet is vigorous and very productive, so crops must be restricted if the wine is to keep any concentration. Budbreak is late, which helps the vine avoid spring frost, and ripening falls in the middle to end of the season, later still when yields are high. Berries are medium to large, round to oval and dark purple, with a clear Cabernet Sauvignon flavour. Powdery mildew is a moderate risk, a trait often blamed on its Carignan parent, but the vine strongly resists botrytis bunch rot. Its ability to cope with heat explains its use in hot, irrigated vineyards. Poor fruit set has reportedly held back its success in parts of South Africa.
Most Ruby Cabernet is made as a simple, fruity, dry red intended for early drinking. Typical wines are dark ruby to purple, with red cherry and plum fruit, soft tannin and moderate acidity, and a slightly rustic edge. In blends it is used to deepen colour and to stretch Cabernet Sauvignon, and much of the crop is sold in bulk for generic red blends. Wines from controlled yields or cooler sites can show more structure and darker, blackcurrant-like fruit, and a few producers in South Africa, Texas, Brazil and Israel bottle it as a varietal wine. Very few examples are made for long ageing, and most are best drunk within a few years of the vintage.
Where it grows
California
The variety was bred for the hot San Joaquin Valley and still sits mainly there, with about 2,400 ha (roughly 6,000 acres) recorded around 2009, far below its 1960s peak. It is used mostly in generic blends.
South Africa
Plantings were about 2,400 ha in 2015, down roughly 9 per cent in a decade. The vines are concentrated in hot, irrigated inland areas such as Robertson and the Olifants River, and the crop is mostly bulk wine.
Australia
About 1,100 ha were recorded in 2008, mostly in the hot inland Riverland, Riverina and Murray Darling regions, where it is used for blending.
Texas and other US states
About 40 ha were recorded in Texas around 2010, with the best examples from higher, cooler vineyards in the Texas High Plains. Small plantings also exist in Virginia, North Carolina and Wisconsin.
Brazil, Israel and Uruguay
Brazil had about 40 ha in 2009, with varietal wines made in the Vale do Sao Francisco and in Rio Grande do Sul. Israel and Uruguay have only minor plantings.