Tetra - Prime Solum

Napa Valley AVA

Bill Hill is becoming one of the wine industry's most respected planters and vintners


The name William (Bill) Hill has been a widely recognized name in California wine circles for more than four decades. His original winery, William Hill Winery, became a top notch Napa Valley entity and was ultimately sold to industry giant Gallo in the mid-1970’s. From that time, Bill Hill has taken a rather unusual path toward becoming one of the wine industry’s most respected (named to Wine Spectator’s Top 50 list in 1996) planters and vintners.

Hill was originally from Oklahoma and early in his career earned a masters in business from Stanford University. Sensing the importance of developing high quality vineyards in numerous microclimates that exist along the Pacific Coastline, he set out to establish himself as one of the top formulators of vineyards in the wine industry. At present, Hill owns and operates a large number of vineyards along various sections of the coastline of California, Oregon and Washington. He has had a hand in developing almost 40 different wineries and vineyard properties, arguably among the finest vineyards in the entire nation. His development company, Premier Pacific Vineyards, owns and operates vineyards that sell to the very top wineries throughout California and elsewhere.

“The simple fact is that Bill just loves dirt,” remarked Kevin O’Brien, general manager for Hill’s new Napa Valley operation named Tetra Winery. “He adamantly believes that dirt is the prime determinant of what winds up in the glass, and that’s what dictates the eventual fate of the winery.” For the record, Tetra means four and refers to both the four individual vineyards used as sources for its wines and also alludes to the fact that four different Bordelaise varietals constitute the wines that make up Tetra’s portfolio.

Since Hill formerly developed the likes of Diamond Mountain Ranch and Mt. Veeder Estates along with other notable properties, it would be easy to expect greatness from fruit he controls directly or though partnership. Such is the case with Tetra Winery, whose vineyard sources include four of Napa Valley’s premier growing tracts.

Fruit from Broken Rock Ranch, Coombsville, Sugarloaf Mountain and Suscol Bench make up the vineyard content for Tetra’s wines. Each vineyard contains a different varietal that is used in the eventual blending of the Tetra wines.

“It is amazing how the different grapes do in different years. One year, the Petit Verdot will be amazing, the next year the Merlot will be sensational. Since we are in the coolest growing area of Napa Valley, the grapes have the opportunity to hang longer and develop their characteristics. This really matters when we do the blending and produce our wine that will have its own distinct personality,” added O’Brien.

Tetra Winery made its debut in 2006 when it produced a miniscule 296 cases. The wines were instant hits and produced some of the highest scores for a first appearance winery ever seen. Since then, additional wines have produced exceptional scores and Tetra Winery is now accepted as one of the premier niche wineries in Napa Valley. Production has remained low, with between 500 – 600 cases being produced annually.

“We prefer to make our wines in the hundreds of cases as opposed to the thousands,” Kevin O’Brien further explained. “This allows us to make truly superior wines, on a par with the really great ones that come out of the valley.”

One of the keys to Tetra Winery’s early success is the winemaking team that Bill Hill has assembled. The team is led by Patrick Mahaney, a 24-year veteran of the Robert Mondavi Winery group. Mahaney’s last eight years with Mondavi found him in the role as Vice President of Global Wine Quality, an incredibly high profile position in the multi-continent company that Mondavi has become. The UC-Davis trained winemaker has played an important role in Tetra Winery’s development and initial early success.

“We have a really top-flight team put together,” concluded O’Brien. “We are on the cutting edge with regard to our wines, but in a really safe mode. Bill Hill is interested in new choices, but safe choices. We will always rely on the Cabernet Sauvignon-based Bordeaux blend, but that blend will vary whenever great fruit is produced in one of our vineyards. We have already seen the possibilities from our early releases, but I think there are more really great wines in the future. Tetra Winery has created a great deal of excitement so far, and we intend to do the same for many years in the future.”


Prime Solum

Prime Solum is Bill Hill’s premium label for which he only produces vineyard designate Cabernet Sauvignon from Napa Valley’s Brokenrock Vineyard, located on the Eastern ridge of the Valley at the foot of Atlas Peak. Brokenrock, named for its remarkably rocky soil, is also Hill’s 90-acre home ranch that is perched on a steep, western-facing slope. The hillside location is blessed with high drainage and low fertility soil and consistently produces wines of unusual intensity and concentration. It is planted predominantly to Cabernet Sauvignon, but there are also smaller plantings of Merlot, Petit Verdot and Cabernet Franc that Hill uses for blending in tiny quantities. Of all the vineyards Bill Hill has developed, none have lived up to his aspirations quite like Brokenrock. It is an extraordinary site that yields extraordinary wine.

“Since we are in the coolest growing area of Napa Valley, the grapes have the opportunity to hang longer and develop their characteristics. This really matters when we do the blending and produce our wine that will have its own distinct personality,” added O’Brien, general manager for Hill's new label Prime Solum.

Prime Solum made its debut in 2009 with just 180 cases of Brokenrock Vineyard Cabernet Sauvignon.

The name Prime Solum is based on the term solum in soil science which refers to the state of the evolution of soil as which it is best for plant growth. Prime Solum means “an ideal place to grow something,” and in this case, Hill’s Brokenrock Vineyard in Napa Valley – the ideal place to grow Cabernet Sauvignon.

Prime Solum’s first wine was an instant hit, garnering an impressive 92 Points from Wine Enthusiast magazine. Since then, the 2010 vintage has been released to receive even higher scores and recognition. Prime Solum is quickly, and quietly, joining the premier niche wineries in Napa Valley. Production has remained low, with between 200 and 400 cases released each year.

O'Brien concluded, “We have already seen the possibilities from our early releases, but I think there are more really great wines in the future. Prime Solum has created a great deal of excitement so far, and we intend to do the same for many years to come.”


Dear Platinum Series Members,

My name is Bill Hill and I am a long time winegrower in California and Oregon. My career has been built upon the well-known principal that the quality of wine is determined primarily by the vineyard. This idea has led me on a 40 year odyssey to understand climates and soils and how they shape and determine wine quality. Along the way, I have had the opportunity to design, develop, farm and make wine from the mountains of Napa Valley, the hills of Western Sonoma, the beautiful Anderson Valley in Mendocino, the bucolic Eola-Amity Hills in Oregon, and the Ocean-cooled Santa Rita Hills in Santa Barbara. It has been a great ride…

To make the best possible wine, it is essential to source from a vineyard with near ideal climate and soils; however, you can’t stop there. The vineyard must be developed in a state-of-the-art fashion in every way. From varietal selection, to plant material selection, soil preparation, and infrastructure, such as trellis placement and technique – all of these things must be optimized. Likewise, the vineyard must be farmed meticulously, following practices that are known to result in high wine quality. All good winemakers know that the character and potential of the wine is largely determined by the time the fruit is harvested. Great winemakers spend a lot of their time in the vineyard!

As if that is not enough, to make the best wine, one must then do everything in the cellar with the same tenacious dedication to perfection that was evoked by the farming. To make the best possible wine, one must start with the great vineyard and then do everything else right.

Over this 40 year career, I have had the opportunity to design over 50 vineyards. Many of them have lived up to my aspirations, but none more so than Brokenrock Ranch. Nestled on the southwest shoulder of Atlas Peak in Napa Valley, this mountain vineyard has it all: Excellent rocky, well-drained soils, lots of sun exposure above the fog line, cool ocean breezes; they all add up to ideal conditions for Cabernet Sauvignon and its varietal companions: Merlot, Cabernet Franc, and Petit Verdot.

For a number of years, it has been my plan to create a single vineyard Cabernet from Brokenrock. I initiated this program with the 2009 vintage and with my long-time friend and winemaking associate, Patrick Mahaney. Patrick has been making wine in Napa for almost as long as I have been growing grapes…he is one of the most talented winemakers I know.

I eventually bottled my new wine under the name: PRIME SOLUM. Solum is a term from soil science which refers to the state of the evolution of soil as which it is best for plant growth. PRIME SOLUM means an optimal place to grow something, in this case, world-class Cabernet Sauvignon.

As you would expect of a Cabernet from Brokenrock, it is intense and concentrated, yet elegant and refined. An alluring ethereal nose introduces you to lush, layered flavors and a level of full ripeness that defines Napa Valley. And so, I present to you the 2010 vintage PRIME SOLUM Cabernet Sauvignon from Brokenrock Vineyard. I hope you will give it a try!

Bill Hill