Oct. 29 (Bloomberg) -- Driving rain rattled the tin-roofed shed in Napa’s Spring Mountain wine district where I was playing grape picker and cellar rat during harvest. No picking cabernet at Cain Winery that morning. Sunny California was elsewhere.

The district’s annual October Touch the Terroir crush camp drew a couple of dozen retailers, sommeliers and me for a hands- on experience to discover what makes Spring Mountain’s famous cabernets special.

For three days I walked muddy vineyards; listened to fermenting juice bubble as Pink Floyd and Latin pop played in the background; and tasted wines at boutique wineries with views to die for.

Wearing yellow slickers, Cain’s Associate Vineyard Manager Ashley Anderson and Spring Mountain Vineyard’s Ron Rosenbrand filled us in on the district’s basics.

Spring Mountain isn’t a peak, it’s an area in the Mayacamas mountain range that separates Napa from Sonoma and that’s home to about 30 wineries, steeply rocky vineyards and underground springs.

“This is the coolest and wettest of Napa’s 14 subregions,” said Anderson. “Warm nights, days cooled by Pacific breezes mean a long, slow, even ripening season and more intense flavors.”

It’s also Napa’s oldest mountain area, with ghost wineries from the 1800s. Late-ripening cabernet sauvignon and related grapes like merlot make up nearly 90 percent of the vines.

Tangled Terroir

In theory, Spring Mountain cabs should show similar taste characteristics that reflect the area’s terroir, but the district’s 1,000 acres of vineyards are diverse -- 21 types of soil at 400-foot (122 meters) to 2,200-foot elevations.

I’ve never thought the wines had a signature flavor profile. Growers, though, extol the specialness of their mountain-grown fruit and their unique winemakers’ virtues.

“Mountain men are freer, tougher, more independent, stubborn and contrarian,” Fritz Maytag, savior of Anchor Brewing Co. and owner of York Creek Vineyards, said at an opening reception. Valley floor vineyards are “the mudflats, like cornfields.”

To my relief, Rosenbrand suggested trading wet vineyards for cellar work, and drove a couple of us down hairpin curves to the district’s grandest estate, Spring Mountain Vineyard. In the late 1800s, it was Miravalle, whose wines won gold medals at World Fairs. Its stately mansion won TV fame in the soap opera “Falcon Crest” in the 1980s and billionaire Jacob E. Safra, a member of the Lebanese banking family, bought it in 1992 along with several adjoining historic plots.

Robot Sorter

In the winery, we admired the new $250,000 machine that selects the best grapes for crushing and took turns raking cabernet skins from stainless tanks (harder than I thought). The weather’s effect was much on winemaker Jac Cole’s mind. Sixty percent of their grapes were still on the vine, and six inches of rain fell during the next 12 hours.

“It’s scary, but as long as sun and wind dry them out, we’re okay,” said Cole. Otherwise, rot could set in. (It didn’t, but the valley floor wasn’t so lucky.)

At a new winery, Vineyard 7 & 8, we compared cabs and cab blends in a domed-ceiling room. I looked for similarities, finding diverse styles and high quality. The wines show rich, bright fruit and more satiny textures and softer tannins than mountain cabs from Napa districts such as Mount Veeder.

Among 2006s, I savored Vineyard 7 & 8 “7” ($75), with its perfumed nose and polished flavors, and Barnett Vineyards’ powerful, chocolaty blend of cabernet sauvignon and cabernet franc ($55).

Delicious 2005s

The 2005s are downright delicious -- especially fresh, floral-scented Guilliams Reserve ($70); smooth, intense Marston Family Vineyard cabernet ($100); complex Cain 5, a blend of five Bordeaux varieties ($100); and silky Spring Mountain Vineyard Elivette ($100), mostly cabernet sauvignon.

None of Spring Mountain’s reds is cheap. Cain winemaker Chris Howell said sales of Cain 5 are down 30 percent from last year, adding, “It costs three to four times more to make mountain wines -- yields are low and work on high-altitude vineyards is harder.”

I found the best wine at my last stop.

As I ducked into the modest wood Philip Togni winery, damp mist hung over the vineyard. White-bearded Togni, 82, was pressing cabernet grapes.

He could care less about rain -- his grapes were all picked by Oct. 1.

“Every new wave of ideas, we’ve ignored all that,” said Togni, who began his career at Bordeaux’s Chateau Lascombes in 1956 and arrived in California 2 years later. “We make wine the way Bordeaux did long, long ago.”

Barrel Samples

We sampled ‘07s and ‘08s from the barrel, and then his daughter Lisa, who works with him, set out a few bottles. Smoky, cedary 2006 Tanbark Hill, his second label, may be the best buy on Spring Mountain -- it can be had for $45.

The main label wine, Philip Togni, is rich, complex, elegant. Cassis-scented 2006 is classic ($90), 2001 ripe and opulent ($110). My favorite is velvety, still-evolving 1991 ($140). Togni aims - and succeeds - in making some of the best and longest-lived wines in California.

Maybe mountain men are the Spring Mountain character after all.

(Elin McCoy writes on wine and spirits for Bloomberg News. The opinions expressed are her own.)

To contact the writer of the story: Elin McCoy at emcwine@gmail.com.

Last Updated: October 29, 2009 00:01 EDT