History
Cabernet Franc is one of the most important grapes in France, particularly in Bordeaux, and the Loire Valley, where one might assume it originated. Yet, genetic and historical studies point to the Spanish País Vasco (southern Basque Country) for its actual place of origin. According to Jancis Robinson’s Wine Grapes, DNA parentage shows that Cabernet Franc has parent-offspring relationships with two ancient cultivars from the Basque Country, Morenoa and Hondarribi Beltza (often confused with Cabernet Franc in the vineyards of the Basque Country’s Txakoli region), and, as such supporting, the hypothesis of Jean-Michel Boursiquot is that Cabernet Franc is a native of the Spanish País Vasco (Basque Country).
In 1997, geneticists John Bowers and Carole Meredith at U.C. Davis revealed Cabernet Sauvignon as the offspring of Cabernet Franc and Sauvignon Blanc—the result of a likely spontaneous cross that happened somewhere in the Bordeaux region. So, back to the original presumptions!
California Cabernet Franc Timeline
Cabernet Franc introduced to California (Sullivan, Companion to California Wine, 1998, supra, at p. 43.)
First-known plantings of Cabernet Franc in Napa Valley’s Detert Vineyard, originally part of the To Kalon Vineyard. (Source: https://vinepair.com/articles/cabernet-franc-rise-in-napa/)
Small amounts of Cabernet Franc began to be planted throughout Napa Valley. As Cabernet Franc usually has a lighter body, with less tannin and acid than Cabernet Sauvignon, it was conventionally blended with Cabernet Sauvignon and Merlot. Cabernet Franc grapes were blended by Robert Mondavi in his 1971 Reserve Cabernet Sauvignon.
Cabernet Franc plantings stood at 1,377 hectares/3,402 acres (1,315 hectares/3,250 acres bearing and 61.5 hectares/152 acres non-bearing) through year-end 2021, representing 0.73% of total vineyard plantings of all California wine grapes.