Since 1978, Marietta Cellars' founder Chris Bilbro has pursued an old-fashioned business model. In an era when wine marketers are in a frenzy for face time on the social network, Marietta skips it. When an enthusiastic fan begged sales manager Sam Bilbro to give him the link to their Facebook page, Bilbro replied that there is none. Just tell your friends. During big weekend events, in fact, they block the driveway with a flatbed truck to deter the tipsy throngs. And there is no tasting room.

Indeed, on the Marietta estate, a collection of modest buildings and 40 acres of vineyard winding back into an Alexander Valley canyon, there's no twittering—only the oinking of a few charismatic little orphaned piglets adopted by winery staff. Marietta's flagship blend, Zinfandel-Old Vine Red, is styled like an old-fashioned "field blend." With dark, woodsy notes leading to warm, brambleberry fruit, it's juicy yet dry, rustic in character but smooth on the palate. Non–vintage dated, the current release is Lot Number 51, and as always, it's remarkably consistent with previous lots. Chris Bilbro learned to cook by taste, the only way that his great aunt Marietta would have it. Now, with no formal training, that's how he builds his wine blends. Bilbro was eventually joined in the business by three sons—some with formal training.

The 2007 Zinfandel starts shy, with hints of cedar and menthol amid warm berries, then gushes boysenberry and blueberry juice, before the soft, warm and finely astringent finish brings it in, refreshing to the last drop. With black cherry and cassis liqueur aromas, the 2006 Cabernet Sauvignon is easy drinking yet refined, with a finish neither chalky nor grippy. The 2006 Petite Sirah is deep purple, natch, with briars and blueberry, a creamy palate and the most aggressive tannins of the bunch. The 2005 Angeli Cuvée is a Zin blend and the luxury equivalent of Old Vine Red—warm brown spice, baked blueberry, soft and silky.

Marietta has no set retail prices, but expect to see Old Vine Red selling for around $12, the varietals around $20 and the Angeli around $28. If you find a good deal, for goodness sakes don't twitter it—bring a bottle to a friend.

Marietta Cellars, Geyserville. No public tasting. Marietta wines may be found in Oliver's, Fiesta and Pacific, and G&G markets, and select local restaurants and pubs. www.mariettacellars.com.

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