Casablanca Valley is a wine-growing region of Chile, located 60 miles (100km) north-west of the country's capital, Santiago. The east-west-oriented valley is roughly 19 miles (30km) long, stretching to the eastern border of the Valparaiso province. It is best known for its crisp white wines, most notably Sauvignon Blanc and Chardonnay, which have gained it recognition as one of Chile's quality wine regions. Pinot Noir, which is responsive to the cooler climates found in this coastal area, is also grown with some success.
Casablanca Valley's first vineyards were planted in the 1980s during the revitalization of the Chilean wine industry. Expansion of vineyards around the industrial town of Casablanca followed, but a lack of water for irrigation (and restrictive local laws relating to this) has halted new plantings for now.
© Jonathan Reeve
Because it is only 20 miles (30km) from the Pacific Ocean at its furthest point, Casablanca Valley is strongly influenced by the cooling effects of the Humboldt Current, which flows up the west coast of Chile from the Antarctic. Cooling afternoon breezes blow from the ocean towards the mountains in the east, filling the vacuum created by warm air rising in the east. The reverse winds in the evening, however, are not sufficiently strong to provide a cool finish to Casablanca days.
Given the valley's location at 33°S (much closer to the Equator than any European vineyard), viticulture here is possible largely because of the oceanic influence, which brings cool morning fog and greater cloud cover than is found elsewhere in the north of Chile. It is this cooler climate that makes Casablanca's white wines stand out from their local rivals. With a longer ripening period, the white grapes have more time to develop greater flavor complexity, while maintaining sugars and acids in balance. This cool climate, while undoubtedly beneficial, is not without its dangers – crops have been seriously damaged in the past by severe frosts in spring.
The sandy clay soils in the area, although free draining and otherwise suitable for viticulture, have been something of a bane for the grape growers of Casablanca Valley. It is thought that the use of chemical fertilizers in the past caused an outbreak of nematodes – microscopic worms that damage vines by feeding on the roots. They thrive in sandy soils just like those of Casablanca Valley, so growers have had to graft vines onto nematode-resistant rootstocks.
The difference between Casablanca's climate and that of Chile's more southerly regions led the prestigious Casa Lapostolle to choose the valley as the exclusive source of grapes for its Cuvée Alexandre Chardonnay. The region is now growing a wide range of white grapes, notably aromatics such as Viognier, Gewurztraminer and Riesling, and is at the heart of Chile's efforts to prove that it is able to excel at more than just red wines.