The millions of tourists who visit Napa Valley each year spend a lot of time driving up and down Highway 29, its north-south thoroughfare. But confined to the vineyards stretched out on either side of the highway, these visitors get few chances to see the vineyards extending up the mountainous slopes, which produce some of Napa’s most interesting wines.
Of Napa Valley’s 16 AVAs (American Viticultural Areas, i.e., officially recognized wine-growing areas), five are actually on the mountainsides. Tourists coming from San Francisco first encounter Mount Veeder in the forested Mayacamas Range to their left, eventually followed by the Spring Mountain and Diamond Mountain districts. On the right, the almost bare, chaparral-speckled slopes of Atlas Peak and Howell Mountain define the Vaca Range. These off-the-beaten-path vineyards are receiving renewed attention from today’s wine drinkers.
“Maybe there’s a part of it that plays into that ‘millennial, authenticity, exploration’ thing,” says Sarah McCrea. Her grandparents founded Stony Hill Vineyard on Spring Mountain in 1943, planting Chardonnay decades before it became popular in California. From her point of view, that urge to explore is partly why winegrowers came to the mountains in the first place.
“Farming in the hills is so different and unique that it attracts a different kind of person, with a different kind of desire,” McCrea says. “So a lot of it is about the kind of people that end up in the mountains being more adventuresome and beating their own path.”
It’s not an easy path. Clearing land and removing the volcanic or sedimentary rocks just to plant the vineyard is harder. Growers may need to build terraces and manage erosion so the sparse soil isn’t washed away entirely.
Once planted, the vineyards are much less uniform than those of the valley floor. A block of vines near the edge of the forest, near a spring, or facing in one direction will require different management than one a few yards away where the trees are absent, the soil is drier, or the slope faces the morning sun more directly.
And for all that work, yields—the amount of grapes each acre produces—are generally lower than on the valley floor.
So what do they get for their trouble? “Typically we find that mountain wines are by their nature certainly more tannic and more structural in general,” says master sommelier Matt Stamp, co-owner of Compline Wine Bar in Napa. “I think the acid and tannin levels in mountain wines tend to be elevated from what you find on the valley floor where you get, a broader, lusher kind of Cabernet.” All those factors mean the wines can often age very well but might be less generous when young. At Compline, Stamp actually divides the Napa Cabernet Sauvignon portion of his list into “mountain” and “valley and lower hillside” sections. He says he might steer a guest who likes Barolo, for example, to the Napa mountain wines.
The characteristics Stamp describes stem from the growing conditions. Varied as they may be, these mountain vineyards have a few things in common. “All the soil in the valley floor got there by being washed down the mountainside,” says Christopher Howell, general manager at Cain Vineyard & Winery in the Spring Mountain District. “So if you know that, you know that most of the soils on the slopes have been washed away. If you have a hillside, odds are the soils are going to be relatively thin.”
Thin soils have fewer nutrients and hold less water, prompting the vines to produce smaller grapes and naturally concentrating the raw material of winemaking. “If the vine naturally wants to produce less you will frequently have wines with a stronger personality. That doesn’t make them better; they could be abrasive or difficult, but they’re generally less easygoing.” Cain’s flagship wine is Cain Five, a blend of the five classic Bordeaux varieties; Howell says it was developed because the mountain-grown Cabernet Sauvignon by itself could be too intense and unyielding.
The other important factor defining Napa’s mountain vineyards is in the air, not the earth. “Fog was covering the valley floor this morning, as it usually does in August and September,” says Sam Peters, executive director for the Howell Mountain, Atlas Peak, and Mount Veeder Vintners Associations. “Everything above 1,400 feet is above the fog, so the mountains don’t experience the temperature swings that the valley might. It might be 10 degrees cooler during the day because of the elevation, but also 10 degrees warmer at night” when the cold air and fog settles on the valley floor.
It’s such a key difference that it’s actually written into the description for the Howell Mountain AVA; to be part of the AVA, a vineyard must not only be on the mountainside but also above 1,400 feet in elevation.
The brighter fruit of valley floor wines stems from a cooling period each night, whereas mountain fruit tends to have a darker fruit expression. Howell says mountain tannins are also riper at the same level of sugar development, so on the palate the wines will have more tannins, but their texture is smoother.
The difference between mountain and valley fruit destroys the myth that Napa Valley wines are all the same. Many wineries actually use a blend of mountain and valley fruit to achieve a balance. Long Meadow Ranch started with vineyards in the Mayacamas Range, but its larger-production wines today blend in 30% to 40% of grapes from its property in Rutherford on the valley floor, which softens the austerity that might come from using only mountain fruit. “We usually pick our grapes at a sugar level that results in a wine between 13% and 13.5% alcohol, so they’re very restrained and balanced,” says owner Chris Hall. “One of the reasons we’re able to do that is because of these mountain vineyards.”
Hall sees a growing interest in Long Meadow Ranch’s mountain vineyards. While the winery has a prime spot on Route 29, he says more and more guests are booking two-hour excursions just to see the Mayacamas Estate: “Anybody looking to explore mountain-grown Cabernet Sauvignon or wines in general has many options if you want to get off the beaten path when you’re visiting Napa Valley.”
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