In 1983, the Anderson Valley in Mendocino County, California, was designated as an American Viticultural Area (AVA). This was back when there were only about 30 AVAs in the United States, as opposed to the 250-plus AVAs that exist today.
The vineyards and the valley
The Anderson Valley AVA is about 24 kilometres long and runs along a narrow valley formed by Anderson Creek and the Navarro River. It is about 1.6 kilometres wide from north to south. As such, it is tucked between the Mendocino Ridge AVA to the south and the Yorkville Highlands AVA to the southeast, forming a neat rectangle (with a bit of fluff on the western edge). Anderson Valley AVA is a subregion of the larger Mendocino AVA.
The Anderson Valley AVA encompasses 23,310 ha, with 994 ha under vine. Within its borders are currently more than 90 commercial vineyards and 30 bonded wineries. Many wineries in Napa and Sonoma counties make wine from Anderson Valley fruit.
Rivers, ridges, and rolling hills: The relatively flat (and fertile) valley floor of the Anderson Valley cuts a fairly narrow path through the region. Beyond the valley, the area comprises rolling hills interspersed with forests of Douglas Fir, California Laurel, and California Redwood Trees, as well as mountain ridges that outline the California Coast Range (topping out at about 762 m above sea level). The mountains and hills form a series of south-facing slopes and many prime viticulture locations.
It is, without a doubt, a pleasant climate
The western edge of the Anderson Valley AVA, known as the deep end by locals, is only 16 kilometres from the Pacific coast. The low-lying, narrow valley is perfectly positioned from here to capture cool ocean breezes and funnel early morning fog inland and upriver. Rainfall is frequently abundant, though it varies from year to year. While daytime temperatures can sometimes reach as high as 38°C for a few days in the summer, the average temperature for a given year is typically 12°C. As a result, the Anderson Valley is one of the coolest wine regions in the United States.
Subregions of Anderson Valley: A Mosaic of Microclimates
Anderson Valley is not a monolithic stretch of vineyards but rather a mosaic of subregions, each with its own unique characteristics. The valley runs roughly 15 miles from Boonville to Navarro, and this stretch is divided into three main subregions: the “Deep End,” the “Middle Reach,” and the “Northern Reaches.”
Deep End:
Located on the western end of the valley, the Deep End is influenced by cool maritime breezes from the nearby Pacific Ocean. The cool climate allows for a longer growing season, ideal for cultivating grape varieties that thrive in slow-ripening conditions. Notable for its rugged terrain, the Deep End is often characterized by steep hillsides and unique geological formations.
Middle Reach:
Positioned between the Deep End and the Northern Reaches, the Middle Reach experiences a balance of maritime influence and warmer temperatures. The soils here vary from alluvial near the Navarro River to more rocky and well-drained slopes.
- This subregion is known for producing wines with a harmonious balance of fruit expression and structural elegance.
Northern Reaches:
The northernmost part of Anderson Valley, this subregion tends to be warmer and drier compared to the Deep End. Soils can range from gravelly and rocky to clay, contributing to the diversity of wines produced. The Northern Reaches are recognized for their distinctive expressions of Pinot Noir and other cool-climate grape varieties.
Soil Secrets of Anderson Valley: Unveiling Terroir Mysteries
The terroir of Anderson Valley is a complex tapestry woven by a variety of soil types, each playing a crucial role in shaping the character of the wines. Understanding these soils provides insight into the nuances that make Anderson Valley wines so distinct.
Alluvial Soils:
Found in the Middle Reach, these soils are a mix of clay, silt, and gravel deposited by the Navarro River. Alluvial soils are well-draining, contributing to the development of concentrated flavors in the grapes.
Franciscan Complex:
Common in the Deep End, the Franciscan Complex consists of shale and sandstone. These rocky soils contribute to the minerality often found in wines from this subregion.
Boekenoogen Series:
Present in the Northern Reaches, the Boekenoogen series includes gravelly loam and clay loam soils. These soils provide good drainage while retaining enough water to sustain the vines through the growing season.
Understanding the diverse soils of Anderson Valley allows winemakers to tailor their viticultural practices to maximize the potential of each vineyard site, resulting in wines that reflect the unique terroir of the region.
Pinot Noir reigns supreme
According to an Anderson Valley Winegrowers Association (AVWA) vineyard census, nearly 69% of the region’s vineyards are planted in Pinot Noir as of 2018. Chardonnay is the second most widely planted grape, accounting for 21% of total plantings, and is used extensively in the region’s sparkling wines. Gewürztraminer (4%), Merlot (3%, mostly grown in the warmer eastern part of the region), Pinot Gris (2%), and Riesling (1%).
Pinot Noir first appeared in the region in 1971, when Husch Vineyards planted 1.01 ha of the heartbreak grape on a small hilltop vineyard known as “the Knoll” Other estates quickly followed suit, including Navarro Vineyards, Lazy Creek Vineyards, and Greenwood Ridge Vineyards. Plantings of Pinot Noir have more than fivefold increased since the mid-1990s, as the undeniable affinity between the Anderson Valley terroir and Pinot Noir has been confirmed.
Anderson Valley Pinot Noir is known for its lively acidity and elegance, as well as aromas and flavours of red and black fruit (raspberry, black cherry, cranberry, and plum), complemented by herbal, savoury, earthy, and floral notes. Navarro Vineyards, Baxter Winery, and Domaine Anderson are among the top Anderson Valley Pinot Noir producers. Outside of the valley, wineries such as Williams Selyem, Littorai, Cakebread, Siduri, and Goldeneye (the Duckhorn Portfolio’s Pinot Noir-focused offshoot) are producing outstanding Pinot Noir from Anderson Valley fruit.
