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Thursday, February 5, 2015

What Makes Sonoma County Special for Wine?

The previous blog post talks about why California is so great for wine grapes. Taking that a step further, why is Sonoma County such a perfect place for premium wines? As mentioned in that earlier post climate and soil are the two key ingredients for producing the best wines.

Sonoma County's Mediterranean Climate

Largely because of the latitude and the brisk waters of the Pacific, Sonoma has a two season climate with a cool, damp winter and a long, warm, dry summer. "Warm and dry" is key to having an excellent growing season for wine grapes. With Sonoma County's western border being the Pacific Ocean there is a distinct cooling influence. This is quite unique and helps make the area special for grape growing. The late night and morning low clouds (what the locals call fog) is nature's air conditioning that keeps summer days temperate and the nights cool. Perfect for wine grapes!

A Sonoma coast beach where it rarely tops 70 degrees in the summer

What's really unique are the micro-climates. A micro-climate is a small area with distinct weather from other nearby areas. During the summer you can find different temperatures and fog patterns within just a few miles. Valleys and hillsides are different. How much a particular locale is exposed to the cool breezes from the Pacific is the key.

It's not unusual to have summer afternoon temperatures of 60 degrees at at the coast and 95 degrees elsewhere in the county. It's also not unusual to have a 30 or 40 degree swing in high to low daily temps. The cooling off at night is great for flavor development in the grapes.

This wide range of summer temperatures allows Sonoma County to grow pretty much every wine variety you'd want. Some grapes like it cooler during the growing season, some like it warmer. It's quite extraordinary to be able grow all the major wine varieties within a few miles of each other.

Remember, if you don't like the weather you can drive to a different micro-climate in a few minutes!

This small vineyard above the valley floor is in rocky
volcanic soil, but with clay running through the middle;
probably an old stream bed


Sonoma County has more soil types than France. Broadly speaking, the soils are related to the ocean, mountains, valleys, rivers, and ancient volcanic activity. There's everything from clay to silt to volcanic rocks, sometimes all within a short distance of one another and even multiple soil types in a single vineyard.

Just like you can drive to a different micro-climate in a few minutes you can often walk to a different soil type.


Grapes have been planted in Sonoma County since the mid-19th century -- not very long by European standards. Sonoma County has a history of timber lands, range land for cattle, and tree fruits. These other agricultural uses were more prevalent until the 1970s when wine grapes became so popular. In the late 1980s the value of grapes exceeded dairy in the county to become the number one ag crop.

Today in the Vineyard

Almost three-quarters of Sonoma County's agriculture value is from wine grapes. There are over 1100 growers and 450 wineries. The most planted grapes, in order by the most acreage, are Chardonnay, Cabernet Sauvignon, Pinot Noir, Merlot, Zinfandel, and Sauvignon Blanc, but there are about 50 grape varieties grown.

Pick up a bottle

Taste our Pacific-driven climate, soils and history. There's a huge choice of wine types and styles. Enjoy.