California is the largest and most important wine region in the USA. It accounts for the southern two-thirds (850 miles or 1370 kilometers) of the country's west coast. (Oregon and Washington make up the rest.) The state also spans almost ten degrees of latitude. With mountains, valleys, plains and plateaux, California's topography is as complex as its climate, offering winegrowers a bewildering choice of terroir.
Californian wines only rose to global renown in the past few decades (notably after the Paris Judgment of 1976). However the state's viticultural history dates back more than 200 years. European vines were first planted here in the 18th Century, as settlers and missionaries made their way up and down the west coast. They brought with them the Mission grape – the vinifera variety also instrumental in establishing viniculture in Central and South America. Although very few Mission vines are to be found in California today, it remains a cornerstone of Californian wine.
The first half of the 20th Century brought war, Prohibition and the Great Depression to the United States. Collectively these suffocated the nation's wine industry. It wasn't until the significant social, cultural and economic developments that followed World War 2 that things began to change. In the 1970s, Californian wine industry leaders brought about renewed winemaking passion in other US states, in turn sparking the national wine renaissance. This period saw a proliferation of new, small-scale wineries throughout the country and the upscaling of longer-established operations. Momentum has continued into the 21st century.
Today, California hosts some of the world's largest wine companies. It is also home to a number of boutique wineries, some of which attract astronomical prices for their cult wines. Whether through mass production or single-vineyard artisanal winemaking, California produces 90 percent of American-made wine. It also supplies more than 60 percent of all wine consumed in the country. A record 211.9 million cases were produced in 2011.
The principal varieties grown in California are Cabernet Sauvignon and Chardonnay. A wide range of traditional European (Vitis vinifera) vines also flourish, including Pinot Noir, Merlot and Syrah. Zinfandel can also be included in the list as it is genetically identical to Tribidrag in Croatia and Primitivo in Italy. Among white grape varieties Sauvignon Blanc is a distant second to Chardonnay. These are grafted to hardy American rootstocks which are resistant to phylloxera. Less well known are American/European hybrids producing wines mainly for local consumption.
Sparkling wines are produced in considerable volume. Many French Champagne houses have set up Califonia wineries. The most famous examples are Moet & Chandon's Domaine Chandon, Taittinger's Domaine Carneros, Roederer Estate in the Anderson Valley and Mumm Napa in the Napa Valley.
Soils and climates vary substantially throughout California. A complex combination of variables are in play. These include altitude, latitude and proximity to the cool waters of the Pacific Ocean. In summer, the cold inshore waters of the Pacific help to create a fog bank just off the coast. As the inland air warms and rises, cold fog is sucked in to fill the space. In extreme cases, fog has been known to travel as far as 100 miles (160km) inland, cooling and refreshing the land as it goes. Mountainous terrain between a vineyard and the Pacific limits the influence of a maritime climate. This relationship can vary widely across the state.
Generally, the cooler regions closer to the coast are better suited to cool climate grape varieties such as Pinot Noir and Chardonnay. Further inland – where the climate is much hotter – some of California's most famous red wine is made from Cabernet Sauvignon. Zinfandel produces some outstanding examples throughout the state.
To sum up the complex climatology, topography and geology of such a large area is impossible. For specific information on each of California's wine regions and AVAs, please use the links to the left.