Steven Kent Winery, 2021 Ghielmetti Vineyard Cabernet Franc, Livermore Valley, California, USA
Cab Franc du Jour #143
For those who have been following this project for some time, you may have noticed that California Cabernet Franc has not featured prominently here. While single-varietal expressions are becoming more common in the state and the variety has received considerable attention in the press in recent years, Cabernet Franc still represents a very small slice of California’s overall viticultural landscape. As of 2023, there are approximately 3,485 acres (around 1,410ha) planted in the state, less than 1% of total wine grape acreage and a modest figure compared to the over 95,000 acres of Cabernet Sauvignon.
When it comes to California Cabernet Franc, commitment matters. The wines that have resonated most here are from producers who have made the variety a genuine part of their identity, rather than those who have arrived at single-varietal Cabernet Franc simply because it is fashionable to do so.
Which brings me to Steven Mirassou, someone who has gone all in on Cabernet Franc. Steven is the sixth generation of America’s oldest winemaking family, whose roots in the wine business date back to 1854. His own winemaking journey began in 1996 when he and his father established Steven Kent Winery in the Livermore Valley, with a strong focus at the time on Cabernet Sauvignon. After returning to California, Steven discovered Kermit Lynch’s retail shop in Berkeley, and many will know that Lynch was among the first in the United States to champion Loire Valley Cabernet Franc, introducing iconic domaines to American consumers and trade alike. Through Lynch’s shop in the early 2000s, Steven began discovering the wines of Charles Joguet, Bernard Baudry, and others, and a passion was ignited.
By the 2006 vintage, Steven made his first single-varietal Cabernet Franc from fruit sourced from the Ghielmetti Vineyard. Struck by the quality and distinctiveness of the variety’s expression in Livermore, and recognizing that it offered a point of differentiation from the vast quantities of Cabernet Sauvignon being produced across California, he began working more closely with grower partners and gradually shifted greater focus toward Cabernet Franc within the Steven Kent range. In 2017, he launched l’Autre Côte Cabernet Franc, a nod to Bordeaux’s right bank and the winery’s flagship expression of the variety. Today, Steven works alongside his son Aiden and wife Beth with about 15 acres of Cabernet Franc from select vineyards across the Livermore Valley, and in 2023 they produced 13 different expressions of the grape, from a blanc de noir to various rosé styles to reds. Beyond the winery, Steven has become a genuine champion for the variety, founding an annual celebration called Cab Franc-a-Palooza that draws producers from across the United States and beyond, and writing and speaking about his affection for the grape through his newsletter and podcast, Wine Saves Lives.
The Livermore Valley
Located in Alameda County and part of California’s Central Coast, the Livermore Valley is one of the state’s oldest wine regions. Even before Napa Valley became synonymous with world-class Cabernet Sauvignon and Chardonnay, it was the pioneering Concannon and Wente families who first established vineyards with these varieties in Livermore in the 1880s. It is estimated that up to 80% of California’s Cabernet Sauvignon and Chardonnay vines can be genetically traced back to those original plantings. Today the valley has around 3,200 acres under vine, roughly 7% of Napa Valley’s cultivated area, with Cabernet Sauvignon and Chardonnay remaining the dominant varieties and only about 60 acres of Cabernet Franc currently planted.
Situated about 50km due east of San Francisco, the Livermore Valley is bound by the Pleasanton and Sunol Ridges to the west and the Altamont Pass to the east. It is the first coastal valley east of San Francisco Bay, and one of the few in California oriented on an east-west axis, forming an oval-shaped bowl roughly 40km long and 18km wide. The valley floor sits at a higher elevation than most coastal valleys, ranging from around 100m above sea level in the west to about 300m in the east, which contributes to a wider diurnal range between daytime and nighttime temperatures. The east-west orientation, combined with this elevation and gradual incline, allows cool air from the San Francisco Bay and Pacific Ocean to funnel into the valley, particularly in the afternoons, moderating temperatures and giving Livermore a slightly cooler overall character than much of Northern California. As a general rule, temperatures cool as you move from west to east along the valley, following the direction and increasing speed of the afternoon breezes.
The majority of the valley floor and lower hillside sites are covered with deep alluvial soils derived from the surrounding hillsides, ranging from gravelly loam and sandy loam to clay loam depending on location. Soils in the western part of the region tend to be lighter and sandier, while more clay-dominant soils appear as you move east. Rich in minerals like calcium and magnesium, with an alkaline pH and good drainage overall, the soils are well suited to viticulture, though the variability across the valley makes site selection particularly important for Cabernet Franc.
Wind and the Future of Livermore
There is a climatic phenomenon unfolding in the Livermore Valley as a result of climate change that may prove significant for Cabernet Franc over the long term. During the warmest months of the year, July through September, rising temperatures in California’s hot Central Valley on the eastern side of the Altamont Pass create a vacuum effect that pulls cool Pacific air into the Livermore Valley, driving afternoon and early evening wind speeds to around 25 to 30km/h before they die down as the Central Valley cools overnight. Grapevines are generally sensitive to wind and can slow or halt photosynthesis under these conditions, which effectively slows ripening and extends the growing season. As a result, harvest in Livermore typically runs about two to three weeks behind Napa Valley, and the fruit that comes in is physiologically ripe but at lower sugar and potential alcohol levels.
As the Central Valley continues to warm, the wind effect in Livermore intensifies, and the growing season lengthens further. Steven has noted that he is now picking both Cabernet Franc and Cabernet Sauvignon on average two weeks later than he was just 15 years ago. It is conceivable that the season could eventually become too short to fully ripen Cabernet Sauvignon, at which point Cabernet Franc, which typically ripens seven to ten days earlier, may emerge as the valley’s most important variety.
The Ghielmetti Vineyard
The Ghielmetti Vineyard is located in the southeast corner of the Livermore Valley, about 8km east of downtown Livermore, making it one of the most easterly sites in the region. The vineyard sits on a gentle west-facing slope ranging in elevation from around 260m at the base to about 290m at the top on the eastern side. Its position just before the Altamont Pass means the afternoon winds arrive here at their most intense, making Ghielmetti one of the windiest and coolest sites in the valley. Steven notes it is typically the last to bud in spring and the last to be harvested in the fall.
There are approximately 3.7 acres of Cabernet Franc here, planted in 1999 with Clone 332, one of the clones originating from the Pyrenees region. Soil types vary across the vineyard blocks, but in the Cabernet Franc block specifically, the soils are a deep, fine-grained Positas gravelly loam derived from sandstone and shale, with a balanced mix of sand, silt, and clay in the topsoil and up to around 50% clay content in the subsoil between 60 and 100cm. Steven manages the vineyard directly as one of the winery’s estate sites, farming it sustainably with drip irrigation in place. Shoot thinning is performed throughout the season, selective leaf removal is carried out on the western side of the canopy to improve sun exposure, and green harvesting takes place at around 60% through véraison.
In the Cellar
The fruit is hand-harvested between 3 and 4am to ensure it arrives at the winery as cool as possible. It is fully destemmed, sorted, and lightly crushed before fermentation in small 1.7-ton open-top fermenters with selected yeast, reaching a maximum temperature of around 27C. Punchdowns are performed throughout fermentation to aid extraction, and the wine spends approximately 28 days on skins in total. The free-run and press wines are blended together prior to aging in mostly neutral 500L French oak puncheons for 14 to 18 months.
Wine Details
Producer: Steven Kent Winery
Region: Central Coast, California
AVA: Livermore Valley
Vineyard: Ghielmetti Vineyard
Soil: Fine, Positas gravelly loam
Alcohol: 13.5%