Bordered by the Pacific Ocean
Sonoma County lies north of San Francisco and is bordered on the west by the Pacific Ocean. The county runs parallel to Napa Valley, and is separated from it by the Mayacamas range.
The area is known for the diverse micro-climates that occur within the crevices and folds of the hillside and valley terrain. With long, dry, warm-but-rarely-hot summer days buttressed by cool nights, ocean breezes and fog drifting into interior valleys, it helps preserve acidity and complexity in the wines and creates daily temperature swings of 40 degrees or more…ideal for a grape’s flavor development.
Another feature here involves the wide-ranging nature of the soil. With the Mayacamas Mountains, the rolling hills of the Carneros, the Russian River Valley, coastal hills and other geographical anomalies, Sonoma County has more soil types than all of France, with soils ranging from rich and loamy to volcanic/rocky and well-drained.
Areas in Northern Sonoma such as the Dry Creek, Alexander, and Russian River Valleys each produce Zinfandel grapes with unique characteristics, yet they share the common link of warm days and cool nights associated with the marine influence of the Pacific Ocean and San Pablo Bay. The Sonoma Valley, which extends along Route 12 from Santa Rosa to Glen Ellen, has 100-year-old vines with deep-rooted systems that protect them against warm temperatures and early ripening.
The extended growing season of the Russian River Valley intensifies the flavors in the fruit, producing very lush, dark plum and boysenberry qualities. Zinfandel from Dry Creek has a distinct core of black cherry and vanilla flavor and aroma, and Zinfandel from Alexander Valley tends to be described as “supple” with plump blackberry and black cherry flavors. As the Sonoma Valley is a slightly cooler region, these wines are quite lush and feature plenty of black pepper and spice.
Sonoma County’s American Viticultural Areas include Alexander Valley, Bennett Valley, Chalk Hill, Dry Creek Valley, Fort Ross-Seaview, Fountaingrove District, Green Valley of Russian River Valley, Knights Valley, Los Carneros, Moon Mountain District, Northern Sonoma, Pine Mountain – Cloverdale Peak, Rockpile, Russian River Valley, Sonoma Coast, Sonoma Mountain, and Sonoma Valley.