The province of Mendoza is the ultimate grape-growing region since 879 wineries are established there and are registered in the National Wine Institute (Instituto Nacional de Vitivinicultura) representing 71% of the total number of wineries registered in the Argentine Republic. This province produces more than 80% of Argentina’s wine from its 15,000 vine-planted hectares. Mendoza’s wine industry increasingly focuses on quality, and on finding the optimum relationship between different varieties and terroirs. Mendoza’s diversity is doubtlessly enviable in this respect.

Grape-growing oases in Mendoza.
In Mendoza, three grape-growing regions may clearly be identified:

LMendoza’s wine geography can be divided into three major oases. However, by carefully studying the territory, one can discover multiple peculiarities within terroirs that are highly different from one another. Each terroir has its own particular location, altitude and soil composition.

Northern Region
The Districts of Luján de Cuyo and Maipú form part of a traditional wine-producing region known as the “prime zone” of Argentine wines. This designation results from the prestigious labels coming from this area, historically regarded as being among the best in Argentine wine production.
In the North, altitudes range from 600 to 700 meters above sea level, with a gentle slope. The ecological characteristics of this region favor the production of white, young, aromatic wines, as well as fruity, red wines for short-term consumption.
Mendoza’s Eastern region is a true wine-producing power considering its vine-planted area and the number of wineries concentrated there. Altitudes range from 750 to 640 meters, and the different zones in this area are substantially distinct in terms of climate, soil and thermal amplitude.
Mendoza’s “prime zone” and the Uco Valley are two of the most interesting regions for the foreign investors who have been continuously operating in the country since 1990. The advanced age and the small size of many of the wine-producing farms in these regions have led to the development of small wineries so in vogue these days.

Central Region
Well inside the first mountainsides of the Andes’ foothills, the Uco Valley presents the highest altitudes at which wines are produced in the province of Mendoza: up to 1,400 meters above sea level. As in the case of Luján de Cuyo and Maipú, this particular area is undergoing an intensive development process thanks to the influx of investments from foreigners, some of whom are making particularly significant investments. The reasons why this region is so coveted are its thermal amplitude and high solar radiation levels. The combination of these factors results in slow and balanced ripening cycles. Thus, both white and red varieties give forth their primary varietal bouquets. Particularly in the case of the red varieties, tannins and color become fixed in the grape’s skin, thus giving the wines intensity and structure.

Southern Region
The City of San Rafael and its surroundings are the last wine producing oases in the Province of Mendoza. The maximum altitude is 750 meters in Las Paredes, going down to 485 meters in General Alvear. In this region we find varieties such as Chardonnay, Sauvignon Blanc, Riesling, Chenin, Tocai Friulano, Semillon, Torrontés, Cabernet Sauvignon, Pinot Noir, Merlot, Malbec, Syrah, Barbera D’Asti and Bonarda varieties which, in turn, form the basis of this region’s wines.

FSource: Wines of Argentina