If you don’t immediately associate California’s Lodi AVA with the likes of such wine grape varieties as Aglianco, Picpoul Blanc, Zweigelt or, for that matter, Verdelho and Verdejo, you’re not alone. But these are just five of the more than 100 wine grape varieties grown in this area, which encompasses seven sub-appellations about 100 miles east of San Francisco Bay and bordering the San Joaquin-Sacramento River Delta.

Billing itself as the Zinfandel Capital of the World and growing the grapes used to produce 40 percent of California’s Zinfandel wines, Lodi has long produced California’s other leading California varieties, including Cabernet Sauvignon, Chardonnay, Merlot, Sauvignon Blanc.

But in recent years the non-mainstream varieties being grown here have started attracting attention from American consumers eager to explore more of their expanding world of wines.

Lodi’s classic Mediterranean climate, highlighted by warm days and cool evenings, coupled with a wide-range of soil types that accommodate a broad array of grape varieties account for part of the vineyard diversity here. But, Lodi’s community of adventuresome, innovative grape growers and wine makers, who are willing to experiment and to stretch the envelope of the region’s wine-making possibilities, are also playing a key role.

Their numbers have been slowly and steadily growing over the past 15 year or so, reports Stuart Spencer, program manager for the Lodi Winegrape Commission.

“Our growers aren’t turning away from the mainstream varieties,” he says. “Instead, they’re trying to satisfy the desire of consumers for wines from other parts of the world that they’ve heard about but have never tasted before. Many of these growers and wine makers are small artisan producers looking to distinguish themselves and develop a niche in the market for less well-known, but interesting grapes and wines.”

One such grower is Ron Silva. His Silvaspoons Vineyards near Galt, Calif., in northeastern Lodi’s Alta Mesa sub-appellation, include a little over 300 acres of wine grapes.

He planted his first variety, Zinfandel, in 1997 and has been growing them under contract for 12 years. In 2000, he planted his first Portuguese variety, Verdelho, becoming one of the first in California to do so

Today about half of Silva’s vineyard ground is devoted to such traditional California varieties as Cabernet Sauvignon, Cabernet Franc, Malbec, Petite Syrah and Pinot Gris. “They help pay the bills,” he says.

The rest are planted to 16 non-traditional varieties. Most are native to the Iberian Peninsula

They include Portuguese whites, like Torrentes and Verdelho, and the Spanish white variety, Albariño. Among his Iberian reds, all from Portugal, are Alvarelhão, Tinto Căo, Touriga Francesa, Touriga Nacional and Trincadeira.

Individual plantings of his non-traditional varieties range in size from his largest, 24 acres of the red French grape, Tannat, and 12 acres of his largest block of white Portuguese grapes to five rows of Mencía, a Spanish red.

Some may require tweaking a customary production practice here and there, Silva notes.

Consider his Rare Souzão, a red Portuguese variety. “It has dark red juice with terrific color and very unique flavor,” he says. “As little as 1 percent of it in a wine blend can make a huge difference in the flavor profile. Also, it’s an extremely late-maturing variety. If I can get 23 ºBrix with it, I’m pretty happy.”

His choice of non-traditional varieties reflects his heritage – his family immigrated to the Bay Area, one set of grandparents coming from the Azores and the other from Portugal – and Alta Mesa’s climate and topography.

“When I walk out the front door of my house and look around, it’s like I’m in the middle of Portugal’s farming area,” Silva says. “The landscapes, the soils, the climate and weather patterns are the same.”

Silva’s variety selection is based on his desire to do things in a very different way.

“People like to experience the new and the different,” he says. “That’s where I fit in. Being a small-scale grower and oriented to high quality, I want to grow grapes for small or boutique wineries that can be used for stand-alone wines or as blenders for consumers who enjoy and appreciate unique flavors, textures and colors.”

Silva markets his Portuguese and Spanish varieties by first gathering half a dozen or wines, which are good representations of the grape variety he’s selling. Then, he hits the road, introducing wine makers to the qualities of the particular variety by inviting them to sample the wines. The idea, of course, is to interest vintners in applying their skills to bring out the best in the variety.

“Just about all my customers have kept coming back for a number of years to buy more grapes,’ Silva adds. “And, a number of them have used the grapes to produce award-winning wines.”

In fact, he’ll hit the road again this year to introduce wine makers to his latest variety, Mencía. Native to northwestern Spain, it’s similar to Cabernet Franc, Silva notes.

He tracked what few cuttings of this variety were available in the U.S. to a nursery in southern California, and he bought all the cuttings he could – enough, he estimates, to produce at most 5 tons when he harvests the fruit for the first time this fall.

Silva is the first in California to grow it commercially. “Mencía will require a lot of experimenting in the winery,” he says. “For example, I don’t know how much, if any, oak it likes or even the best Brix at harvest. I’d like to work with a small hands-on winery to create a wine that best represents the Mencía grapes from my vineyard and that consumers will enjoy.”

Silva, who hires contracted labor for pruning and harvesting work, has five full-time employees who help look after his vineyard as well as his breeding herd of Angus and Hereford cattle. He describes his vineyard operation as well-managed and efficient.

“I’m very fussy about my vineyard and keep it immaculate,” he says. “My customers get a very clean product from well-maintained vines.”

Silvaspoon Vineyards complies with the Lodi Rules of Sustainability, he notes. Cultural practices include the use of cover crops throughout his vineyard to help control weeds and improve soil tilth. It’s a locally-blended mix of barley, fava beans, beans, mustard, annual rye, vetch and wheat.

Once each year, prior to disking or mowing, he treats every other row of vineyard with compost to build soil nutrient and organic matter levels and improve soil texture. Made from a combination of dairy waste, manure and straw from a local horse facility and beef cattle auction yard, he spreads it at the rate of 12 tons per average row.

Although he has land to expand his vineyard, Silva likes the current size. It allows him the time to do what he enjoys – whether walking his vine rows or operating his fork lift to load a bin of grapes onto a customer’s truck.

“I like being out in the vineyard,” he says. “I know every block of grapes and how many plants are in each row. A half a day of disking or mowing is therapeutic to me. Whether doing that or being with the pruning crews, there’s no better way to really see your vineyard.”

Still, Silva hasn’t completely shut the door on possible expansion.

“I could add another 80 acres of Cabernet Sauvignon and make more money,” he explains. “But, planting just one acre of new variety, that’s what excites me and gets my blood flowing. When it comes to a new variety, it’s like I can’t help myself. I have to plant it.”