San Juan Creek District
January 26, 2021
The Paso Robles American Viticultural Area (AVA) was established in 1983 and at that time there were 556,765 total acres with a little over 5,000 under vine. In 1996, the AVA expanded by 52,600 acres and then again by 2,635 acres in 2008. In 2007, a petition was sent to the federal government to establish 11 districts within the Paso Robles AVA. In the same year, a conjunctive labeling law (AB 87) was passed, which preserves the brand awareness of the Paso Robles AVA by ensuring that “Paso Robles” will always be seen in conjunction with the districts on wine labels. These 11 districts within the Paso Robles AVA were finally approved in 2014.
The Paso Robles Wine Country Alliance is continuing to focus on all 11 AVAs in this blog through 2021, in alpha order.
The San Juan Creek American Viticultural Area (AVA) within the greater Paso Robles AVA may be the oddest shaped of the 11 AVAs in Paso. In large part, because it follows the San Juan Creek Valley that represents the easternmost AVAs as it touches the Estrella District to its north and the Highlands District to its south.
San Juan Creek was named after Saint John which was a popular place name in old California. As one of the earliest land grants in San Luis Obispo County, it was named San Juan Capistrano del Camate. This amounted to about 30 square miles of land but in 1846 was deemed unallowable by the United States government. It eventually was parceled out and purchased by individuals. Early historical accounts had this creek being known as both San Juan Creek and the Estrella River, but today it is well established that San Juan Creek is a tributary that comes together with the Cholame Creek to form the Estrella River.
At the confluence of the two creeks is the town of Shandon. Once named Starkey, it changed its name to Cholame in the late 1880s. Shandon’s population was sparse in the late 19th century and remains below 2,000 citizens today. The San Juan Creek area has long been a ranching, vineyard, and field and row crop farming community. At one point attracting a fledgling farmer, Walter Knott, into growing produce for the ranch hands in the area and selling what was not consumed. By 1920, Knott moved to southern California to begin a berry farm which eventually became Knott’s Berry Farm.
It was not until the 1960s when commercial grape farming found its way to San Juan Creek. In 1963, Robert Young planted a vineyard in Shandon. Mr. Young is known as the first new commercial grape grower in the region post Prohibition, as well as the first to incorporate a commercial irrigation system in Paso Robles. In 1971, Darryl John moved to Shandon and planted the San Juan Vineyard for Louie Lucas of Lucas & Lewellen. Early varietals planted included Zinfandel, Carignan, Cabernet Sauvignon, Sauvignon Blanc, Muscat, and Chenin Blanc.
The San Juan Creek AVA consists of about 26,000 acres with a little over 3,000 acres under vine. Elevations in the district range from 980 feet to 1,600 feet above sea level, from river valleys to foothills, respectively. The landscape of the district is evident from the effect of the San Andreas Fault and adjacent San Juan Fault. There is a lot of uplift and subsequent erosion of the mountain ranges. This provides for some stunning land formations that are very photogenic. San Juan Creek follows the path of the San Juan Fault, which has fractured the earth.
The broad alluvial plain of the AVA consists of mostly loamy sands, gravelly to sandy clay loams, and a few clays on the older alluvial fans and terraces. These create moderately draining conditions in the vineyards which encourage moderate vigor in the vines. This also provides an environment for deep soil rooting depths and some moderate to high water stress. With the abundance of sunshine in the San Juan Creek AVA, moderate yields are common with earlier harvest dates than in the cooler regions to the west.
The San Juan Creek AVA is about 32 miles from the Pacific Ocean and within a rain shadow of the Santa Lucia Coast Range, so it has a warmer and more continental climate than some of the other Paso Robles AVAs to the west. There is a descending air movement that takes place in the rainy season down the lee slopes of the coastal range, as well as the La Panza Range to the south. As a result, rainfall decreases from about 20 inches annually in the Templeton Gap District to around 10 inches in the San Juan Creek AVA. That is a 50% reduction in rainfall in less than 20 miles.
San Juan Creek can get exceptionally warm during the summer as it is a Region III – IV on the Winkler Scale, although the nights still get quite cool with an average diurnal temperature swing of 35 – 40 degrees Fahrenheit. This growing degree climate is suited to several Bordeaux varieties of wine grapes, including Cabernet Sauvignon, Merlot, and Cabernet Franc. However, many are seeing success with Petite Sirah and some Italian and Spanish varieties as well. There are not any winery brands associated with the San Juan Creek AVA, however, the vineyards located there are prime source vineyards for a multitude of wineries throughout the Paso Robles wine region.