For Steve Scofield, his family's share in a vegetable farm was also a ticket to the Clean Plate Club.

"I'm not a huge fan of vegetables, to be perfectly honest," Scofield said. "But it's been really cool. It was just important for us to feel like we were buying directly from a local farmer. And it's broadened our palates, so to speak. I've eaten a lot more vegetables than I normally would."

Scofield and his wife, Sue Maas, are part of a small but growing group of Twin Cities residents who are members of more than 40 "community-supported agriculture" (CSA) farms ringing the metro area. That represents a nearly 30 percent jump from last year alone, said Brian DeVore, communications coordinator for the Land Stewardship project, which publishes an annual regional CSA guide.

That increase, and attitudes like Scofield's, have caught the eye of Health Partners. The health insurer is running a test this year to try to confirm anecdotal evidence that participation in CSAs leads to a healthier diet, and by extension might reduce health care costs.

"We know if somebody is eating more produce, they're going to be healthier on average, all things being equal," said Marcus Thygeson, vice president and medical director of consumer health solutions for Health Partners. "If we can help people live healthier lifestyles, we know we'll be improving their health, and reducing health care costs. That's good for members, it's good for employers paying health care costs, and it's good for society."

Food fascination takes off

Many factors drive people to join community supported ag groups. Members say they want to have more trust in what's on the table, or support local farmers, or reduce the amount of food that is shipped vast distances to stores, or some combination of all three. Members also say that CSA membership is a way for city folk to understand where food comes from. Many groups require members to help with planting, harvesting and deliveries.

"This is the ultimate food with a face on it," said DeVore.

This time of year, even though the ground is frozen, the competition for area CSA shares has a hothouse quality.

Patty Wright, who runs Spring Hill Farm with her husband near Prairie Farm, Wis., said she expects more than 90 percent of their 150 members to return every year.

Scofield and family are joining Big Woods Farm near Nerstrand, Minn., for the fifth summer.

DeVore said people were calling for the 2009 CSA guide in December -- not long after last season's final delivery of root vegetables.

Paul Hugunin, coordinator for the Department of Agriculture's Minnesota Grown program, said that new CSA farms will probably sell out their memberships, despite the uncertain economy. The program's list of CSA farms in the state jumped from 27 last year to 39. Last year, there were 6,071 Google hits on the program's CSA listings.

Growing interest in local and organic produce is apparently not only boosting CSAs, but kitchen gardening as well.

When the State Horticultural Society offered a class in winter seed-starting, it wound up having to offer three, said community outreach coordinator Vicky Vogels. This spring the society is launching a project that will provide low-income people with a "garden in a box" -- a 3-foot-by-3-foot frame, soil and seedlings that will yield tomatoes, peppers, eggplant, beans, herbs and other edibles.

"There's huge interest in this right now," said Tim Sether, of Rivard Companies, which is making the frames for the project.

Idea hails from Madison

CSAs are particularly popular around Madison, Wis. There, Physicians Plus Insurance Corp. in 2005 began offering $200 premium rebates to member families who joined CSAs. The program appears to have been the first of its kind in the country. In 2006, the first full year of the program, 972 members got the CSA rebate; heading into this season, 1,460 will qualify, said Physicians Plus marketing manager Scott Shoemaker.

If people are motivated to eat "healthier foods, exercise and practice preventive health measures, they're going to be healthier in the long run and need less health management down the road," Shoemaker said. "They'll go in to the doctor less. And costs will go down."

In the Twin Cities, Health Partners last year surveyed about 25 CSA members through the season at a weekly produce drop-off site. Participants took the Health Partners health risk assessment, which probes a wide range of health conditions, risk factors and lifestyle features, at both ends of the summer. Participants' "health potential scores" appeared to increase more than the scores for people who didn't belong to CSAs, Thygeson said.

This year, Health Partners is expanding the study to involve 200 individuals or families who are members of 10 area CSAs. If researchers find that CSA members have higher or improving scores, Health Partners might use CSA membership to help shape health plans, possibly similar to what has been done in Madison.

As with most things, there are some downsides to belonging to a CSA. Members say they get too much produce, or things that are too far out of the green beans and tomato tradition. Kale and kohlrabi are the most frequent examples. Bok choy runs a close third. Scofield said his wife's soup recipe redeemed the kale.

"Raw, we'd gag eating some of this stuff," he said.

Scofield added that the benefits of a CSA membership are more than nutritional. They provide a sense of community, and add a little joy to the chore of picking up food.

"The thing we miss the most, when the harvest season ends," he said, "is that we have to buy all our vegetables at the grocery store."

Bill McAuliffe • 612-673-7646