California can trace its wine roots to San Diego, where Franciscan missionaries led by Junipero Serra planted the state's first vineyard in 1769. Of course, California was then part of a Spanish colony referred to as Mexico. San Diego's commercial wine production began in the late 19th century, only to be destroyed by Prohibition. Shortly after prohibition, the Rizzo family resumed production at Bernardo Winery. San Diego's wine industry growth remained stagnant until the 1990's, but has seen exponential growth over the past decade.
Though several wineries source grapes from other California growing regions, a majority of San Diego's wine production comes from the two American Viticultural Areas (AVA's) within the county: San Pasqual Valley and Ramona Valley.
The country's 4th AVA, established in 1981. the 9,000-acre region is California's smallest AVA and has yet to reach its potential. Its desert-like climate is moderated by the proximity to the Pacific Ocean, which creates high diurnal temperature variations but generally keeps growing season tempeatures below 95 degrees Farenheit. San Pasqual Valley's well-drained, granite soils provide great growing conditions for warm-climate varieties including Tempranillo, Sangiovese, Syrah, and Viognier. Most of the vineyards are controlled by Orfila Vineyards & Winery, who is credited with putting this region on the international map.
In stark contrast to San Pasqual, Ramona Valley is the country's 162nd and wasn't approved until 2006. The region encompasses 89,000, almost 10 times that of its northern neighbor. The valley is mostly enclosed by mountains, though its west-east orientation still allows cool ocean air to moderate its generally hot climate. The average elevation here is 1,400 feet, which keeps the valley free of the fog that plagues the nearby coastal regions. Its soils are mostly well-drained, deep sandy loam and sandy clay loam, offering moderately fertile growing conditions for its vines.
San Diego Urban Wineries have changed the wine scene in San Diego drastically. The group's motto, "bringing grapes from the country, making wine in the city", is telling. By developing winemaking facilities and more importantly, tasting rooms and restaurants, in populated areas, these wineries can capitalize on increasing wine consumption in a larger marketplace. Many of these wineries source their grapes from regions outside of San Diego, such as Napa Valley or Guadalupe Valley, but hopefully their success will spur more attention and vineyard plantings in San Diego County itself.