Uco Valley Wine Region Guide

Geography and terroir

Overshadowed by the (semi) active Cerro Tupungato volcano, the Valle de Uco has no equal in South American viticulture. The development of its versatile terroir is a relatively recent phenomenon: over 29,000 hectares are now planted in the zone, which is more than double the amount that was cultivated in the late 1990s.

Meanwhile, almost every leading producer in Mendoza has invested in the infertile, high-potential soils of the Uco Valley, where cool nights and mountain breezes yield elegant wines of incredible precision and verve.

Indeed, few destinations in Argentina can achieve delicate fruit flavors and vibrant acidities so easily. This is one of the key reasons why Bordeaux’s A-list has invested so much capital in the valley—Michel Rolland, Francois Lurton, Laurent Dassault, and the Bonnie family of Malartic-Lagravière are all semi-permanent residents here.

Geographic and Climatic Attributes

The valley is approximately 80 kilometers southwest of Mendoza city, stretching from Tupungato in the north to San Carlos in the south. Meandering for some 70 kilometers between these two subzones, it closely follows the course of the Tunuyan River and its life-giving irrigation. This is an essential part of viticulture in the valley – average rainfall is less than 200mm per annum in this dry continental climate.

On the other hand, the intensity of sunlight encourages high levels of phenolic ripeness; astringent tannin is seldom an issue in Argentine viticulture. This is further accentuated by the high-altitude climats (vineyard sites) that climb to 2000 meters in certain places. This combination of intense sunlight and high elevation produces a broad range of wine styles that, despite their differences, rarely lean into overripeness. Balance and harmony are the key priorities today.

You can see this across the valley, particularly in Tupungato’s dry whites. The most exciting of several subzones now being feverishly developed in the region, its clay-limestone terroir delivers Argentina’s finest Chardonnay and Sauvignon Blanc. These rich-in-minerals, free-draining soils are extremely infertile, encouraging low yields and helping to control plant vigor.

The most important winemaking districts, Gualtallary and La Carrera have demonstrated that Mendoza should not limit itself to reds. Indeed, the top Chardonnays are beguiling and much-loved for their Burgundian finesse and aromas of citrus, grapefruit, and honeysuckle. As elsewhere, diurnal temperature variation ensures that ripeness does not come at the expense of losing acidity. Without it, high-quality winemaking would be simply impossible at these low latitudes.

Meanwhile, sustainability drives investment in the region, sponsoring a diverse range of initiatives, from conversion to organic methods to increasing biodiversity. Bodega Santa Julia, for example, has installed a solar park with 20,000 panels, reducing its need for fossil fuel-based energy. At the same time, rising summer temperatures have led to reduced snowfall in the Andes, lowering the amount of available irrigation water. As a result, Domaine Bousquet has pioneered a ‘Biofilter’ project designed to recapture and recycle wastewater.

Franco Bastias, head of agronomy & sustainability at Domaine Bousquet, says:

“Through a process of biological treatment, we will be able to capture the wastewater and clean it by utilizing the latest biofiltering technology to the point where we believe it will be portable. We will then reuse the water at the winery for irrigation and other needs,”

He also added:

“We believe Domaine Bousquet will be the first winery to filter water to the point of reutilisation as a portable resource. In addition, a wonderful byproduct of capturing all the wastewater is organic waste from the winery: grape skins/stems.”

It’s another milestone for the formidable talent pool transforming the Uco Valley.

Winemaking and regional classifications

The Uco Valley has no paucity of raw human talent – and capital – at its disposal. Neither does it lack architectural masterpieces: cutting-edge wineries such as Bodega Zuccardi blend seamlessly into the landscape despite their striking facades and clean lines. Inside, you’ll find the latest sophisticated winemaking equipment juxtaposed against cavernous barrel cellars and glass-fronted tasting rooms. It is all mightily impressive.

Many of the region’s global investors cluster together in Tunuyán, where the Andes rise directly from the vineyards in the central part of the valley.

There are six distinct subzones, including:

• Los Arboles
• San Pablo
• Vista Flores
• Villa Seca

It is even possible to practice dry farming in the wetter parts of Los Arboles, although climate change is increasing the need for irrigation. Nevertheless, producers in Tunuyán make a wide range of styles, encompassing structured reds, dry whites, and a growing volume of traditional method sparkling wine.

Diamandes, Casa Bianchi, and Michel Rolland have proven that Chardonnay, Syrah, Cabernet Sauvignon, Cabernet Franc, Viognier, and Sauvignon Blanc can all thrive in these alluvial soils, celebrated for their complex flavors and striking freshness.

Meanwhile, some of Argentina’s best and award-winning Malbec is produced from old vines that occasionally surpass the Lujan de Cuyo in finesse and floral perfume.

Artisanal Winemaking Techniques at Diamandes

However, in terms of winemaking, there is little to distinguish the Uco Valley from its peers and neighbors in South America. At Diamandes, for example, workers hand-harvest the Chardonnay berries and press them slowly to extract pure juice free of phenolics. This philosophy guides winemakers worldwide, from Beaune to Napa Valley.

The juice is then vinified in French oak barrels without malolactic fermentation – the conversion of malic to lactic acid is viewed as undesirable in hotter climes. The base wines are then matured in 50 percent new barrique for 12 months, adding structure, texture, and depth to the white wine. Like all great Argentine Chardonnays, it offers a balance of rich fruit and racy acidity, merging the best elements of the Burgundy and New World traditions. The apricot-scented Viognier, meanwhile, has more than a whiff of Condrieu.

However, Mendoza’s true celebrities are found in the vineyards of San Carlos to the south. It contains some exceptional parcels of old vine Malbec, judiciously harnessed by men like Sebastian Zuccardi to produce stunningly refreshing wines—La Consulta and Paraje Altamira are the two leading subzones, renowned for their calcareous soils and cooler mesoclimate.

Here, in these stone-covered topsoils, Malbec, Cabernet Franc, and Syrah yield outstanding red wines: some very prestigious and expensive bottles are made in San Carlos, including Zuccardi’s ‘Finca Piedra Infinita’ Gravascal. Single-vineyard Malbec, often fermented and aged in neutral concrete, has become the height of fashion in a relatively short time.

Uco Valley gastronomy

Mesmerizing landscapes and superlative Malbec have put Valle de Uco on the international map. As a result, the area is brimming with high-end hotels and restaurants, where a jet-setting clientele enjoys the best local food and drink. The culinary offering, however, is rarely limited to grilled meat; a sophisticated mix of European and Argentine influences tends to steer kitchens in 2024. Highlights may include chard pastry, veal casserole, fresh shellfish, lamb navarin, and flan with dulce de leche (milk caramel). Or, best of all, take a leisurely picnic in the vineyards.