Humboldt County is a wine-growing region around the city of Eureka, just north of Mendocino County in California. The boundaries of the wine zone are the same as for the administrative area of the same name. Some interesting cool-climate examples of Cabernet Sauvignon, Merlot, Syrah and Zinfandel are produced, along with Pinot Noir. Small amounts of white grape varieties including Chardonnay, Sauvignon Blanc and Riesling.
Around 150 acres (60 hectares) of vineyards are scattered around the region, clustered along the banks of its many rivers and particularly around the riverside towns of Orleans, Hoopa and Willow Creek. Generally, grapes are grown in the narrow river gorges and on the valley slopes. The vineyards and wineries are often surrounded by the giant redwood trees that grow throughout Humboldt County. In the north of the county the mesoclimates tend to be more influenced by cool breezes off the Pacific Ocean.
Humboldt County is cooler and wetter than much of the rest of California. The climate is characterized by cold, rainy winters and mild, foggy summers, and the styles of wine made here reflect this.
Given the size of the wine region, there is a large diversity of soil types. Loamy silt soils can be found along the riverbanks, while the vineyards in the hills sit on pockets of dark, rocky shale. These soils retain daytime heat that the vines absorb during the colder nights, helping the ripening process.
Humboldt County's rugged terrain means that only small parts of the region are suitable for the cultivation of grapes. Because of this, the wineries here tend to be small and boutique in nature, with cellar doors offering wine tastings for visitors to the area.
Most of the Willow Creek AVA lies within Humboldt County.