It took losing her job for Margaret Davenport to fully understand that bigger is not necessarily better, and that starting over can be energizing -- even in her mid-50s.

Davenport became internationally known as the winemaker at Sonoma County's Clos du Bois Winery, producing everything from the heralded Marlstone proprietary red blend to oceans of Chardonnay. The pay was generous, the perks attractive; magazine advertisements featured her image and words.

In late 2002, Davenport saw several senior managers lose their jobs, including Clos du Bois' general manager and its senior vice president of production. Four months later, in April 2003, she was gone, too, "allowed to retire at 55," Davenport says, after 15 years at the Geyserville winery.

Now 57, Davenport has the enthusiasm of a cellar rat pressing her first load of grapes. With retirement has come freedom -- to make Pinot Noir for her own brand, Davenport & Co., and to consult for others, most notably Passalacqua Winery in Healdsburg, where her expertise helped put its 2002 Old Vine Dry Creek Valley Zinfandel ($29) on The Chronicle's Top 100 Wines list for 2004.

"Clos du Bois underwent a complete change in culture, in corporation direction," Davenport says. "Yet (my departure) was a huge burden lifted. When I started at Clos du Bois in 1987, it was producing 175,000 cases a year. By the time I left, production was 10 times that. We grew 20 to 30 percent several years in a row in the 1990s. I was burned out.

"I went into winemaking for the hands-on aspect; I want to know each and every barrel, adds Davenport. At Passalacqua, she will produce approximately 4, 200 cases from 2004; 100 cases were made of the 2003 Davenport & Co. Keefer Ranch Russian River Pinot Noir ($50), to be released in early 2005.

Jason and Noelle Passalacqua last year purchased the former Pezzi King Vineyards tasting room in Dry Creek Valley and built a winery. Jason's Aunt Edith Passalacqua owned a Healdsburg winery in the 1930s; his father, Tom, grows Cabernet Sauvignon near the winery.

"For me, it's been a mentorship," Jason says. "I've learned so much from her. I said to her, 'Look, I'm going to ask you so many questions -- not because I'm questioning what you do but because I want to know how things work. ' "

Life away from Clos du Bois has also given Davenport more time with her partner, Kristen Johnson, an anesthesiologist, and their daughter, Sofie, 6. Sofie was 10 months old when Davenport and Johnson adopted her from an orphanage in Guatemala.

Davenport and Johnson plan to plant a small vineyard near the house they built in the rugged Rockpile appellation near Dry Creek Valley. "We may make our own wine, or send the fruit to Passalacqua, or to others. We have lots of options," Davenport says.

And yet another new start.