St. Helena AVA — What Everyone Should Know

Where is the St. Helena AVA?

The St. Helena AVA is in the northern half of the Napa Valley AVA, centered around the town of St. Helena. The AVA extends past Highway 29 on the west, up to the Mayacamas mountains and the Spring Mountain District AVA. It crosses Silverado Trail in the east, extending some distance in to the foothills of the Vaca Range, but not reaching the Howell Mountain AVA. It’s southern border is abuts the Rutherford District AVA and the northern, the Calistoga AVA.

St. Helena AVA History

The St. Helena AVA is the cradle of the Napa Valley wine industry. There, in 1861, Charles Krug founded his winery there, it’s now the oldest wine estate in Napa Valley. He’d been making for others, including George Yount, for several years. Krug’s marriage in 1860 to to Carolina Bale brought a nice dowry, 540 acres of her family’s Bale Rancho land. It’s there that he began to plant vines—the Mission variety first—and to make wine. Completion of the the massive stone winery, still part of the estate today, came in 1872. A decade later, Krug established the valley’s first tasting room.

The Historic Redwood Cellar at Charles Krug Winery

But, before all that, in 1860, George Belden Crane, had successfully planted Mission vines and built a small cellar. He made his first wine in 1862. By 1874, he’d expanded the vineyard and his volume was 500,000 gallons per year. Today, the Dr. Crane Vineyard, now 21 acres of vines, is owned by Andy Beckstoffer. It’s red, Bordeaux-variety fruit is highly sought after.

Jacob Beringer

David Fulton Winery lays claim to being the oldest, continuously family-owned and -operated winery in Napa Valley. It was also established in 1860. The winery says the stone cellar he build in 1861 was the first within the city limits.

in 1875, Jacob Beringer bought vineyard land across the street from Charles Krug, where he was foreman. Beringer’s cellar was completed in 1877. With its beautiful grounds and historic wine cave, Beringer is one of the area’s top sites for visitors. And, though the company has been owned by Treasury Wine Estates for some time, Mark Beringer, great-great-grandson of Jacob, is chief winemaker.

St. Helena AVA Climate

As with the rest of Napa Valley, St. Helena has a warm-summer, Mediterranean climate. That provides a long, dry and sunny growing season. Spring and autumn are mild. And there’s scant precipitation outside of winter.

The lack of humidity and growing-season rain minimize disease pressure. The most common threat to the grape crop is spring frost. Therefore, wineries can generally allow the fruit to hang as long as they like. Wine style is largely determined by the producer, not the weather.

Though the climate of Napa Valley is generally similar, it does vary somewhat from one AVA, or vineyard, to another. Overall, St. Helena is the warmest of Napa’s AVAs during the day, because the surrounding mountains trap heat and the AVA is furthest from any avenue of cooling breezes, be that the San Pablo Bay and Petaluma Gap influence to the south or the Chalk Hill and Alexander Valley wind gaps to the north.

That does not mean, though, that the St. Helena AVA is without wind. In fact, wind speed can be particularly high north of town where the Vaca and Mayacamas Ranges converge. That constriction of air flow brings the Venturi effect to bear, substantially increasing wind speed.

The combination of warm days and high winds in the evening creates a massive diurnal shift. The cold nights allow the vines to rest and maintain the grapes’ stores of malic acid. Thus, the wines can have great fruit and color, but also reasonable freshness.

An old, yet still producing, in the historic Hayne Vineyard of Chase Cellars

Soils of the St. Helena AVA

Napa Valley has an extremely complex mosaic of soils. They began forming during the Jurassic period and significant changes occurred as recently as about 10,000 years ago, when sea levels dropped and San Pablo Bay gradually receded to more or less its current level. Mt. Konocti, a volcano in the Clear Lake lava field, of which Mt. St. Helena is also a part, last erupted just 11,000 years ago.

The St. Helena AVA alone has 21 different soil types. A single vineyard might have several soils. Those may call for different grape varieties, clones, and root stocks. Vine training, leafing, irrigation, and harvest dates will also vary accordingly.

Most of the soils are either alluvial or fluvial. Alluvial soils washed down over millennia from the mountains on either side of the valley. “Benches” form on the low slopes, where the largest rocks and gravel settle. Fluvial soils formed as the Napa River and other streams flooded and receded, depositing silt, fine gravel, and organic matter from upstream.

The Vaca Range is of volcanic origin, so its bench and alluvial fan are too. But there’s a variety of volcanic materials there, from fine ash to large rocks. The Mayacamas includes both volcanic and sedimentary soils, so material eroded from its slopes can be either, or a combination of the two.

The granularity of St. Helena AVA soils varies from gravelly and well-drained to loam that’s deep, fine, rich in organic matter, and water-retaining. The former is common on the benches, the latter more typical to the valley floor close to the river.

Topography and Facings

Since the St. Helena AVA spans the valley, it includes slopes on both mountain ranges. But those ranges don’t present one, single slope with a consistent facing. So, in addition to the valley floor flatlands, there are slopes of varying steepness facing every which way.

The valley floor gets sun throughout most of the day, though, if its close to one of the ranges, it may be shaded in either the morning or afternoon. Of course, southern facings get a lot more sun than northern. Eastern get morning sun and western get the more intense, afternoon sun.

Wine Styles

The St. Helena AVA’s warm days, long growing-season, and generous sunlight make it an excellent spot for robust red wines grapes, such as Bordeaux varieties, Zinfandel, and Petite Sirah. When it comes to whites wines, Sauvignon Blanc the most-planted by far.

A number of other varieties would also do very well there, especially those native to places with similar climates, such as southern Italy. But, they wouldn’t yield the same prices Cabernet Sauvignon does. As a hedge against global warming though, some growers are experimenting with other grapes.

AVA Details

Latitude: 38.505°

Altitude: 195’ to 603′

Climate:

warm-summer Mediterranean
3,550 degree days; Winkler-Amerine Region III
1,970 biologically effective degree days

Annual Rainfall: 40 inches, almost all during winter

Total Acres: 12,000

Vineyard Acres: 6,800

Number of Vineyards: 400+

Median Vineyard Size: 17 acres (approximate)

Primary Grape Varieties: Cabernet Sauvignon, Cabernet Franc, Merlot, Syrah, Zinfandel & Sauvignon Blanc

Primary Viticultural Challenge: spring frost, dry growing season

Historic Wineries and Vineyards You Can Visit

Appellation St. Helena, the AVA’s association, has more than 50 winery members. They range from small, family-owned wineries to super-sized estates. There are organic vineyards, wineries with art, places that are great for picnics, and others catering to high-end experiences. To plan your visit, you can look at the Napa Vintners’ listings, or you can contact me for an itinerary customized to your preferences.

The Town of St. Helena

The town of St. Helena, population 5,800, has become a destination itself. Main Street (Highway 29) features handsome, period architecture and a wealth of (non-chain) shopping and dining options. Other attractions include the Robert Louis Stevenson Museum, the Michelin three-star Restaurant at Meadowood, and Bale Grist Mill Historic State Park.

Just north of town is the Greystone campus of the Culinary Institute of America. Its huge, stone building—affectionately called “Hogwarts” by some—was built as a winery in 1899. It’s best-known wine-producing tenant was Christian Brothers, based there from 1945 to 1989. The school offers consumer classes, houses a very large and amusing collection of corkscrews, a cook’s shop, a cafe, and a restaurant.

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