What You Should Know about the Oakville AVA in Napa Valley

by Fred Swan - Guest Blogger


The Oakville AVA is one of 16 nested within the Napa Valley AVA. Oakville is among the most important as well, especially with respect to Cabernet Sauvignon. The region has a very long viticultural history and is home to some of Napa Valley’s most respected vineyards and producers.

Where is the Oakville AVA?

Oakville is in the center of the Napa Valley AVA. It is the 4th AVA from the south and also 4th from the north. It covers a two-mile breadth of the valley floor and extends 500 feet up the Mayacamas bench and 1,000 feet up the Vaca.

Map of Oakville, courtesy of Oakville Winegrowers

Climate and Geography

Though Mediterranean climates are very rare globally, most of coastal California and its wine regions have one. All of Napa Valley, including Oakville does. The result is a long, sunny growing season almost completely devoid of rain. There is low-to-moderate frost risk early in the season, mostly dealt with by fans and sprinklers. Late season offers little pressure from disease. 

Should rain be forecast in early fall, the grapes are almost always sufficiently ripe to harvest ahead of time. When not, drying breezes and warm afternoons prevent rot and mildew after the rain, so producers can harvest when they like. Producers can make the style of wine they prefer, rather than that which weather forces upon them. 

During the growing season, Oakville can get quite warm in the afternoon. Temperatures in the low-to-mid 90s are common. However, nights cool down dramatically, preserving acidity in the grapes and forcing al fresco diners to don sweaters. This cooling results from cold Pacific Ocean air, which passes through the Petaluma Gap and San Pablo Bay, then blows through Carneros and up into the valley.

That marine air also brings fog that can linger until late morning. The fog further chills the fruit. It also protects the vines from morning sun. This again slows depletion of acidity, accumulation of sugars, and allows slow, gentle, phenolic ripening.

Annual rainfall is more or less the same as in Bordeaux, 35 inches. However, in contrast to Bordeaux where it often rains during the growing season, Oakville gets most all its rain in winter and a bit in spring. That, along with drying winds and cloudless skies, means judicious irrigation may be necessary.

Aspect to the sun in Oakville varies east to west. The Vaca bench gets no morning sun, but plenty from midday until early evening. The valley floor offers the most sunny hours. The Mayacamas bench gets morning and midday sun, but those mountains shade the vines from direct sun in the late afternoon and evening.

Soils

Oakville soils also vary from east to west. The Vaca Range is mostly volcanic. So, Oakville’s eastern bench largely consists of volcanic gravel and ash eroded from the hills above. There are also some small zones of alluvial soils. The Mayacamas bench is gravelly too, but has much less ash. That range is largely sedimentary, old sea floor. Both benches tend to be well-drained.

The valley floor has some gravel on either side, material washed down from the respective benches. But much of the flat area features deeper and more fertile soils, fluvial deposits from the Napa River which runs more or less north-south and bisects the AVA.

Grape Varieties

While all Napa Valley AVAs grow red Bordeaux varieties and most focus on them heavily, the majority at least dabble in other grapes. There’s much less of that in Oakville. It’s just too perfect for Cabernet Sauvignon, Merlot, Cabernet Franc, and Sauvignon Blanc.

Oakville Wine, Great for 150+ Years

The 11.887-acre land grant given George Yount by General Mariano Vallejo on behalf of the Mexican government in 1836 extended all the way into what is now Oakville. Yount soon became the first man to plant grapes in Napa Valley. His vines were further south, in what is now the Yountville AVA. But, in 1877, grapes were planted in a portion of the northern section on land which Charles Hopper had purchased for his daughter, Missouri. Now owned by Beckstoffer, fruit from the Missouri Hopper vineyard is still in high demand.

But the vineyard which is arguably Oakville’s most famous was planted even earlier. In 1868, Hamilton Crabb planted grapes on the property he’d named To Kalon. A century later, knowing the quality of the site, Robert Mondavi chose it for his winery. Robert Mondavi Winery, now owned by Constellation, still owns much of the vineyard. But portions are owned by Beckstoffer, Detert, Opus One, and the MacDonald family. (The latter owned much of it well-before Mondavi.) Also pre-dating Robert Mondavi Winery are the Sauvignon Blanc vines in their To Kalon I-block. They are the oldest producing vines of that variety in North America and make stellar wine.

Robert Mondavi Winery To Kalon Vineyard, courtesy of Robert Mondavi Winery

A Critical Mass of Critical Successes

As good as Beckstoffer Missouri Hopper and To Kalon are, they now find themselves in a small crowd of epic vineyards, producing high-scoring, cult wines. At the western edge of the To Kalon Vineyard are the Martin Stelling Vineyard and within it Far Niente. Just south of that is Martha’s Vineyard from which Heitz has made legendary wines. Head further up into the Mayacamas and you’ll find Harlan Estate, Promontory, and Futo.

Across Hwy 29 to the east from Robert Mondavi Winery is Opus One. To its north is the John C. Sullenger Vineyard and then Turnbull. Areas to the south of Opus One include Cardinale and a vineyard owned by Luc Morlet. 

Moving east across the AVA, are Groth, Bond, Screaming Eagle, Tench, Rancho Pequeño, Harbison, and more. Dalle Valle, Joseph Phelps–Backus, Peter Michael–Au Paradis, Vine Cliff and others are on the Vaca bench.

If you’d like more detail on where Oakville vineyards are located, Vinous sells an excellent map.

Oakville Cabernet Sauvignon

The specific character of any Oakville Cabernet Sauvignon will depend on the particular vineyard it comes from, the producer, and the vintage. Generally speaking though, the climate and soils of Oakville allow the Cabernet Sauvignon to reach full, phenolic ripeness every year. That means the wines will be deeply colored and taste primarily of nicely ripe cherry, currant, and berry fruit. The fruit leans more toward black than red. Many wines will only show aromas and flavors of fruit accented by those coming from oak barrels, such as chocolate, spice, vanilla, and caramel. Some will also have savory notes, such as bay leaf, underbrush, and crushed rock. It is extremely rare for wines from Oakville to show flavors associated with underripe grapes, such as green leaves and bell pepper.

Individual producers tend to have particular ripeness levels they like to achieve. That means body and alcohol levels vary from one winery and tier of wine  to the next, but are generally consistent for a particular winery from year to year. The range is medium to full body and 13.5% to 15.5% alcohol. Tannins are rich, but soft or velvety rather than firm or grainy. 

The wines are almost always drinkable immediately. Most will be best after three or more years in the cellar. The best wines can improve for more than 20 years if cellar conditions are good.

Fast Facts about the Oakville AVA

AVA Approved: 1993

Nested within: Napa Valley AVA, North Coast AVA

Latitude: 38.4367° (similar to Alicante, Spain)

Climate: warm-summer Mediterranean

Winkler-Amerine Degree Days: transitional, Region II - III

Average Annual Rainfall: 35 inches

Acres under vine: approximately 4,700

Primary Red Varieties: Cabernet Sauvignon, Merlot, Cabernet Franc

Primary White Variety: Sauvignon Blanc

Try some Oakville Cabernet

JJ Buckley always has some of the most iconic Oakville wines on hand. Here are a few examples.

 2012 Paul Hobbs Cabernet Sauvignon Beckstoffer To Kalon Vineyard

 2016 Robert Mondavi Winery Cabernet Sauvignon To Kalon Reserve

 2015 Dalla Valle Cabernet Sauvignon Estate

 2016 Rudd Vineyards & Winery Samantha's Cabernet Sauvignon

 2015 Paradigm Cabernet Sauvignon Oakville Estate

 2017 Patria Ranch Avoyelles

 2013 Aiken Oakville Cabernet Sauvignon

 2018 Turnbull Wine Cellars Cabernet Sauvignon


JJ Buckley guest blogger Fred Swan is a San Francisco-based wine writer, and educator. His writing has appeared in The Tasting Panel, SOMM Journal, GuildSomm.com, Daily.SevenFifty.com, PlanetGrape.com, and his own site, FredSwan.Wine (formerly NorCalWine) among others. He teaches at the San Francisco Wine School. Fred is founder of Wine Writers' Educational Tours, an annual, educational conference for professional wine writers. He also leads private wine tours and conducts tastings and seminars in person and via Zoom. Fred’s certifications include WSET Diploma, Certified Sommelier, California Wine Appellation Specialist, Certified Specialist of Wine, French Wine Scholar, Italian Wine Professional, Napa Valley Wine Educator, Northwest Wine Appellation Specialist, and Level 3 WSET Educator. He's been awarded a fellowship by the Symposium for Professional Wine Writers three times.