Though twice as large as Napa Valley, Sonoma County is home to about 250 wineries, compared to Napa's 400. More Chardonnay vines are planted in Sonoma County than any other varietal. Of the red grapes, Cabernet Sauvignon is the most widely planted. Sonoma's climate shifts from moist Pacific Ocean coastline to dry inland areas. It may seem counterintuitive, but in Sonoma the warmer plots are typically in the north and the cool places in the south, where the temperatures are moderated by coastal winds and fog. To account for its distinct microclimates, Sonoma County is further divided into 13 sub-appellations, including Alexander Valley, Chalk Hill, Dry Creek Valley, Rockpile, Los Carneros, Russian River Valley and Sonoma Coast. As the name suggests, Chalk Hill is distinguished by its chalky volcanic-ash soils where Chardonnay and Sauvignon Blanc excel. Dry Creek Valley has long been known for its Zinfandel, but Cabernet Sauvignon and Syrah are on the rise here as well. The cool conditions in Los Carneros, meanwhile, have helped it earn a reputation for Pinot Noir, Chardonnay and sparkling wines. One of the newer appellations in Sonoma, Rockpile is perched above the fog on rocky soils that demand the most from the vines, helping them produce powerful, sun-warmed Zinfandel, Syrah, Petite Sirah and Cabernet Sauvignon. Pinot Noir has found a happy home in the fog-shrouded vineyards of the Russian River Valley.
Major grape varietals: Cabernet Sauvignon, Chardonnay, Zinfandel, Merlot, Pinot Noir, Syrah, Sauvignon Blanc, Cabernet Franc, Sangiovese, Pinot Gris
Notable sub-appellations: Alexander Valley, Chalk Hill, Dry Creek Valley, Rockpile, Los Carneros, Russian River Valley and Sonoma Coast
Mendocino County
Long known for its towering redwood forests, Mendocino County now boasts a new claim to fame: a thriving wine industry. In particular, Mendocino County is becoming known for its organic wines. Twenty-five percent of the grapes grown here are certified organic. Mendocino touches on Sonoma County at its southern edge and is hemmed in by the Coastal Mountain Range on one side and the cooling Pacific Ocean on the other. Most of Mendocino's grapes grow in the inland part of the county, in the valleys and along the Russian and Navarro Rivers. The big three wines produced here are Chardonnay, Cabernet Sauvignon and Pinot Noir, along with Syrah, Zinfandel, Merlot and Sauvignon Blanc, among others. The county is divided further into 10 sub-appellations, including Anderson Valley, McDowell Valley, Redwood Valley and Cole Ranch. Vast temperature fluctuations in the Anderson Valley have helped it earn a reputation for excellent Pinot Noir; Riesling, sparkling wine and Gewurztraminer are its leading whites. In Redwood Valley, the reddish soil and cool-climate spell success for Cabernet Sauvignon, Zinfandel and Barbera.
Major grape varietals: Cabernet Sauvignon, Pinot Noir, Chardonnay, Syrah, Zinfandel, Merlot, Sauvignon Blanc, Petite Sirah, Riesling, and Grenache
Notable sub-appellations: Anderson Valley, McDowell Valley, Redwood Valley and Cole Ranch.
Lake County
Before Prohibition put an abrupt stop to things, Lake County produced more wine grapes than any other California County. Today, after decades of painfully slow recovery, the wine country around Lake County is growing by leaps and bounds. Cabernet Sauvignon has the most plantings, followed by Sauvignon Blanc and Merlot, and Lake County is earning a reputation for its Petite Sirah as well. The vineyards surround the largest natural lake in California, Clear Lake, and reach into the cooling elevations of Mount Konocti, a dormant volcano. The nearness of the big lake moderates the temperature in the vineyards. The soils in this county are distinct enough (range from sandy loam to cinder ash and red volcanic soils) to have warranted four distinct sub-appellations: Clear Lake, Guenoc Valley, Red Hills and High Valley.
Major grape varietals: Cabernet Sauvignon, Merlot, Petite Sirah, Sauvignon Blanc, Chardonnay, Zinfandel, Barbera, Sangiovese, Syrah, Cabernet Franc
Notable sub-appellations: Clear Lake, Guenoc Valley, Red Hills and High Valley