Behind a modest Catholic church in Sonoma County sits a little-known vineyard that’s also one of the most influential in California. 

Jess Lander, San Francisco Chronicle, October 31, 2022

The beefy, gnarly and 130-year-old vines of Cloverdale’s St. Peter’s Church Vineyard are the unsung heroes of the Rockpile region, an appellation known for producing intensely flavored Zinfandels that rank among the best in the world. 

The vineyard had an unlikely rise to fame. Clocking in at only 5 acres, it’s in a northwest Sonoma County city that’s not exactly in the lexicon of notable Wine Country towns. The oldest vines on the acreage were planted in the 1880s; it’s unclear when the church assumed ownership of the vineyard. 

It took more than 100 years for the site to make a name for itself. In the early 1990s, St. Peter’s Church parishioner Jack Florence Jr. was starting out in vineyard management and convinced the pastor to let him take over the farming. He wanted to sell the grapes to more reputable wine programs, and in 1994, he landed a breakout deal with the vanguard Zinfandel producer Rosenblum Cellars in Alameda.

Founder Kent Rosenblum, who led the country’s modern day Zinfandel boom in the 1980s, started to produce a limited bottling of St. Peter’s Church Zinfandel that was an immediate hit. “It couldn’t have fallen into better hands than Kent’s,” said Florence. “He really was the first one to put it on the map.”

That same year, Florence, along with his longtime partner and renowned California vineyard manager Ulises Valdez Sr., planted the first St. Peter’s Church franchise vineyard. He transported cuttings (also known as a clone) from the old vineyard and budded them over rootstock high in the rugged and remote hills of Dry Creek Valley to the west. It was one of the first modern day plantings in what later became the Rockpile appellation. 

When Florence’s neighbors noticed his success, they proceeded to plant other vineyards nearby — perhaps most notably, the Boticelli vineyard — also with St. Peter’s budwood. Soon, Rockpile formed its identity as the land of big and brawny Zinfandels. No longer viewed as an extension of the Dry Creek Valley, the region received its official designation in 2002. Today, Rockpile is one of the smallest wine regions in the country with roughly 160 acres of vineyards that overlook Lake Sonoma. 

“It kind of jumpstarted the appellation because wines from this area were all Zinfandel and it was all the same clone,” said Florence. “There was consistency. People immediately knew what they were getting with Rockpile.”

Rockpile vines are planted at elevations ranging from 800 to 2,100 feet. They benefit from a winemaker’s dream combination of ample sunlight above the fog, and cool temperatures from the lake and other maritime influences, which allow for a long and slow ripening. 

But when it comes to dissecting Rockpile’s fame, the region’s pioneers, like Florence, give most of the credit to the St. Peter’s Church clone. 

Words like “dense,” “concentrated,” “dark” and “intense” are commonly used to describe the clone. Winemaker Jeff Cohn, who used to make wine for Rosenblum and still sources a small amount of fruit from the original St. Peter’s Church vineyard for his personal label, pointed to notes of black cherry, tarragon and black licorice. 

“It ages incredibly well,” he said. “It’s a hotter area, and sometimes in those hot areas, wines don’t age as well, but this wine just continues to live on.”

For the past four years, most of the vineyard’s Zinfandel has gone to Napa’s Elyse Winery, which specializes in both Zinfandel and old vines. “It has these awesome textures, like when you lick the roof of your mouth and it’s almost slippery,” said Elyse winemaker Russell Bevan. “The complexity is magical. Take a sip and you think there must be a slice of pumpkin pie somewhere nearby.”