Those who want to delve into our nation's best wines rightfully focus on Napa Valley cabernets. Those seeking our nation's best wine values should take a look to Napa's northerly neighbor.

Lake County is home to bargain bottles featuring a wide range of varietals: sauvignon blanc, syrah and petite sirah in particular plus some outlandishly low-priced cabernet.

The prices are at least partly a result of lower land costs, but the quality comes from the soil and the sun.

"The soils are incredible compared to the vast majority of Napa," said veteran grower Clay Shannon, owner of Shannon Ridge Winery. "I have farmed 4,000 acres in Napa, and there's a lot of heavy, heavy clay. Up here we have a lot of well-drained soil with medium potassium and high calcium, with a magnesium deficiency. That's the kind of soil that grows some of the world's best fruit."

Those conditions are what lured Shannon, who has grown grapes all over Sonoma and Napa, to Lake County. He has not been alone. Industry mainstay Kendall-Jackson was an early adopter, actually a Lake County start-up.

Jed Steele, who crafted K-J's Vintners Reserve chardonnay in the early 1980s, was so enamored of the potential that he opened his own eponymous winery south of Clear Lake, the source of the county's name. Besides Shannon, another esteemed grower, Tuck Beckstoffer, has established a foothold there, while larger concerns such as Guenoc (named after a Lake County valley), Trinchero, Benziger and Hess use the area's grapes in multicounty varietals.

Part of the allure is the low cost of land (and thus of grapes farmed there). Shannon said the 1980s and '90s prices of $3,000 to $4,000 an acre are gone but even today the prices range from $15,000 to $20,000 per acre (compared with $250,000 and more in Napa).

The vineyards are scattered all around California's largest natural lake. Shannon opted for two higher-elevation areas northeast of Clear Lake. "In the hills we get more daylight, but it's 5 to 13 degrees cooler," he said, "and you're downwind from a lake that's 22 miles long. The winds start at 1 p.m., and the air just gets cool.

"Couple the great soil with warm days and cooler nights, and it makes for great tannins and great color."

That's certainly the case with Shannon Ridge's Ranch Collection wines, which are marvelously complex for $12, especially the juicy, layered sauvignon blanc.

The latter varietal has been Lake County's shining light, with Line 39 a perennial screamin' bargain at around $10 and stellar, slightly spendier offerings from Cartlidge & Browne, Tuck Beckstoffer and Six Sigma.

But Lake County reds are coming on strong. Steele's Shooting Star syrah and Shannon Ridge's grippy, grape-y petite sirah and sturdy cab provide fabulous value at around $13. For a few bucks more, Guenoc's Lake County petite is quite tasty.

What's especially promising is that these worthy wines are being made in a nascent vinous region. And the folks doing the trial-and-error work come armed with 21st-century knowledge about growing grapes and fermenting them.

"We had a cabernet bloc that wouldn't get ripe," Shannon said, "so we planted some chardonnay and sauvignon blanc in those spots. We have young vines and are just starting to learn about some areas."

Follow Bill Ward on Twitter: @billward4