By Rick Riozza
Many of our wine loving readership continue to wax poetic when it comes to their favorite mountain vineyards. Sure—the valley’s vineyards are gorgeous with soft flowing hills of oak trees, nut trees, and the colorful vineyard leaves of autumn; but, that readership claims the fruit of high mountain vineyards are “closer to heaven and taste as such”
Approved as an American Viticultural Area (AVA) in 2013, Moon Mountain is one of Sonoma County’s wildest places, set along the Mayacamas Mountains’ western flank above Sonoma Valley, where vineyards effortlessly outnumber wineries. It borders Napa Valley’s Mount Veeder to the east.
Moon Mountain elevation rises from 400 to 2,300 feet. Of its total expanse of 17,633 acres, only 2,000 or so are planted, mostly to Cabernet Sauvignon, Chardonnay, Zinfandel and other reds, including Pinot Noir, which is grown predominantly at Hanzell Winery. The soils are largely volcanic, rich, red and well-draining, with pumice tossed about here and there.
Why would anyone care about a new wine region within Sonoma? Well, if you’re fond of high elevation Cabernet Sauvignon and Zinfandel, like our readership is, you might really enjoy the wines from this area. Moon Mountain continues to deliver hauntingly intense wines; reminiscent of the other famous mountain wine regions of California such as Howell Mountain and Mount Veeder. The stuff coming out of there is exciting, like making wine on the moon!
What makes grapes grown in vineyards at higher elevations special compared to valley-grown grapes in the same region? It’s a combination of increased solar rays, greater (or sometimes lesser) temperature fluctuations, scarce water resources, dramatic weather patterns, and good old-fashioned steepness.
Christine Hanna, of Hanna Winery, states, “Moon Mountain wines lead with more savory notes; black olive, anise, even lavender. Their fruit is dark and brooding, blackberry mixed with coffee and dark cocoa.
“I think Moon Mountain does Bordeaux varieties best. Cab Sauv is a natural at this elevation, giving us all those unique flavors I mentioned. Cabernet Franc loses its tooty fruity valley floor profile to become much more complex, Malbec is very dark and inky, and Petit Verdot is a tannic Titan up there – great as a blender. Even Merlot expresses better at elevation, losing its sometimes weedy and herbal aspect and gaining darker fruit flavors and tannin.”
The major producers who source from Moon Mountain vineyards include Kamen Vineyards, Petroni Vineyard, Haywood Winery, Hanna Winery, Hanzell Winery, Robert Biale, Turley, Ledson, Mountain Terrace Vineyard, and J. Baldwin.
And the popular well known vineyards on the Moon include: Frederick’s Vineyard (used by Turley), Compagni-Portis Vineyard (used by Bedrock Wines), Monte Rosso Vineyard (used by Louis Martini Winery).
So this place is named for Moon Mountain Road, which runs through the area – itself a reference to Sonoma, which means ‘valley of the moon’ in the local Native American dialect. Vineyards are well-established throughout the mountainous area, covering around 1,500 acres (600 hectares) of hills and ridges.
Moon Mountain is located up in the hills outside of the city of Sonoma. Because of its location to California’s most historic wine growing areas you can find some of the oldest living Zinfandel vineyards, including the aforementioned Monte Rosso Vineyard from the 1890’s (now owned by Gallo and used by brand Louis Martini).
If you ever get a chance to go there, you’ll want to take the rugged Cavedale road or Moon Mountain Drive to see stunning views of Sonoma Valley. Before the name Moon Mountain came to be, many of the producers in the area wanted the region to be called Mount Veeder North, since it’s next door on the Western slopes.
Okay, it’s the nerd attack—read on if you’re so inclined: A wine’s tannin structure and acidity are predominately developed in the vineyard—rather than during the winemaking process—and they are mainly impacted by the vines’ particular exposure to the sun and by the temperature shift the vineyard sees from day to night. As you move upward in elevation, the density and intensity of the solar rays grows. For every 1,000-foot gain in elevation, the level of UV rays increases by 10-12%, which forces the fruit to develop thicker skin, leading to greater color concentration and stronger tannins. Temperatures can also increase with elevation.
This AVA is one of the warmer parts of Sonoma County due to its inland position. Winds from both the Pacific Ocean and San Pablo Bay in the south bring cooling maritime influences to the vineyards, but by the time the winds have traveled across the valley floor they have warmed considerably. During the summer and fall, vineyards towards the top of the mountain can be up to 20 degrees warmer than those on the valley floor, leading to more concentrated flavor profiles in the fruit
The warmer climate here means that Moon Mountain District has a longer growing season than other parts of Sonoma Valley, with earlier bud-burst in the spring and a longer hang-time for the grapes in the fall.
Cold air tends to drain off the hillside vineyards into the valley, reducing the risk of damaging frosts and allowing for a long, slow maturation period. As a result, Moon Mountain District grapes have a good balance of sugars and acidity leading to well-balanced wines.
While Monte Rosso includes ten different grape varieties spread over more than 100 small blocks and is the source for an array of fabulous wines, it is the old-vine Zinfandel that has made the vineyard legendary.
Among Zinfandel lovers, Monte Rosso is legendary. First planted in the 1880s, Monte Rosso is recognized as one of the oldest vineyards in California. The wines are powerful, perfumed, and striking a luxurious balance between voluptuous blackberry and blueberry flavors, sophisticated minerality, and spice, it is a profound and potent expression of old-vine Zinfandel. A Turley or Biale Zin is absolutely Zin-full. Cheers!
