General Information: The Mendoza Province is one of Argentina's most important wine regions, accounting for nearly two-thirds of the country's entire wine production. Located in the eastern foothills of the Andes, in the shadow of Mount Aconcagua, vineyards are planted at the some of the highest altitudes in the world with the average site located 1,970–3,610 feet (600–1,100 meters) above sea level. The principal wine producing areas fall into two main departments-Maipú and Luján which includes Argentina's first delineated appellation established in 1993 in Luján de Cuyo. The pink-skinned grapes of Criolla Grande and Cereza account for more than a quarter of all plantings but Malbec is the regions most important planting followed closely by Cabernet Sauvignon, Tempranillo and Chardonnay. Mendoza is considered the heart of the winemaking industry in Argentina with the vast majority of large wineries located in the provincial capital of Mendoza.
Climate:Mendoza's climate can be characterized as arid; however, with extensive irrigation the surrounding landscape sustains cultivation with Mediterranean characteristics. Most precipitation in Mendoza falls in the summer months (November–March). Average temperatures for January (summer) are 32 °C (90 °F) during daytime, and 18.4 °C (65 °F) at night. July (winter) the average temperatures are 14.7 °C (58 °F) and 2.4 °C (36 °F), day and night respectively. Despite the intensity of agriculture, made possible due to irrigation from major rivers, Mendoza's annual rainfall is only 223.2 mm.
Soil:The soil of the Mendoza wine region is primarily alluvial composed of loose sand over clay. Mountain rivers, including the Desaguadero, Mendoza, Tunuyán, Diamante and the Atuel Rivers, provide ample water supplies from melted glaciers in the Andes. Nearly 17,000 boreholes scattered throughout the region provide the equivalent of an additional two rivers' worth of water flow to the area. A system of irrigation channels, canals and reservoirs (some dating to the 16th century) help sustain viticulture in this semi-arid desert region.
Grapes:The pink-skinned varieties of Cereza and Criolla Grande have historically formed the backbone of the Mendoza wine industry and today still account for around a quarter of all vineyard plantings. Used primarily for inexpensive jug wines and grape concentrate, their importance has steadily declined as the Mendoza region focuses more on the export of premium wine varietals. Malbec has emerged as the most important variety followed, in planted acreage, by Tempranillo, Cabernet Sauvignon and Chardonnay.