Each spring, flower lovers for miles around flock to Sherwood Gardens to gaze at its now-famous array of 80,000 tulips.

But come Memorial Day, the tulip-gazers are gone, and the garden is transformed from a palette of vibrant color to a blank - if not completely clean - slate.

What few outside of the surrounding streets of Guilford know is that Memorial Day is not the end of the garden's splendor, but the beginning of a quieter, more casual custom that keeps Sherwood Gardens blooming for several more months and transforms its neighbors into summer horticulturists.

Once the tidy, elegant beds of tulips are through for the season, freewheeling clusters of annuals take over the landscape, courtesy of a small group of volunteers who take part in an "adopt-a-plot" program that started a dozen years ago.

If oil magnate John W. Sherwood is the inspiration behind the well-established tulip tradition in the gardens that bear his name, it is Johns Hopkins physics professor Bruce Barnett who is the mastermind each summer of its lesser-known festival of flowers.

"In a different life, I could have been a farmer instead of a physicist," says Barnett, 58, who grew up on a farm in Morrow, Ohio, outside of Cincinnati. He was part of a team of scientists that in 1995 discovered a subatomic particle known as the "top quark," an elusive and fundamental building block of matter.

But on the streets of Guilford, he is famous for more than physics.

In 1990, he put his agrarian instincts to work in Sherwood Gardens. He sought permission from the Guilford Association to plant flowers in the space after the grandeur of the tulips had faded and left the vacant plots fallow and dry.

"It began to just turn brown and grow up into weeds," says Ray Jenkins, 71, who with his wife, Bettina, keeps a summer plot planted with pink nicotiana flowers. When the Jenkins moved to Guilford 20 years ago, Sherwood Gardens was anything but glorious during the summer months. "There were times when I was afraid it was going to go up in flames."

These days, the soil is well-watered and tended, courtesy of Barnett's army of volunteers.

"The garden itself has transformed from essentially a desert during the summer and fall into an absolute showcase," says Richard H. Franke, a business professor at Loyola College. He and his wife, Elke, keep two plots in the garden and have participated for a decade.

Volunteers give the credit to Barnett, who began the summer plantings on his own.

Each spring, Barnett assigns volunteers their plots, takes their flower orders and orchestrates a large neighborhood planting during Memorial Day weekend. This year, neighbors spent $2,500 on flowers - a tax-deductible expense - planted with mulch, fertilizer and peat moss provided by the Guilford Association.

Although most of the plots are spoken for, Barnett cares for those that aren't. That includes his patch, featuring leafy coleus in the center, and 1,500 white impatiens that form a handsome border throughout Sherwood Gardens.

"He's the master planter of the park," says Elke Franke, a dean at Immaculata College in Immaculata, Pa.

A summer stroll through Sherwood Gardens offers a panoply of blooms - 20,000 were planted this year - from impatiens in pink and white, to zinnias in red and orange, to cosmos and canna lilies.

"It's very exuberant, rather than the very elegant military type of thing we have with the tulips. ... It seems so much more creative," says Elke Franke.

Showing off a long, narrow plot planted with pink and purple cosmos, orange and red cannas, marigolds on each end and zinnias along the border, Elke Franke steps into the dirt to prune some young plants. "Every year, I feel like I give birth," she says. "It's my babies."

'It's an evolution'

Summer gardening has indeed sparked a new cycle in the life of the park, say many participants. Each spring after the annual tulip-dig, prospective garden parents gather at a potluck supper at Barnett's home just around the corner from Sherwood Gardens to begin the season. They will have another celebration in mid-October, when it is time to dig up the annuals and prepare the beds once again for tulips.

A variety of different flowers and planting methods makes for a constantly changing garden scene. "As you go through the summer, you say, 'Gee, this is really the prettiest plot.' But two weeks later, it's a different one," Barnett says. "It's an evolution."

During Memorial Day weekend, the garden is a-bustle with activity - more than 1,000 bags of mulch littering the grounds, bright pallets of flowers strewn everywhere - as neighbors go about the messy but fulfilling task of planting their plots.

"We've made a party of it," Frank McNeil, 40, says of the Memorial Day planting. He and Paul Fowler, 39, invite friends over to their Guilford home to form an "assembly line" of digging, fertilizing and planting. This year, Fowler says, it took 100 hours.

"We did a red, white and blue thing because of 9-11. ... That was on our minds," McNeil explains, pointing out a plot planted with red salvia, white begonias and purplish-blue ageratum.

The ritual draws amateur gardeners from outside Guilford, too. Sculptor Tina Paquet-Estes and her son Edison Estes, 3, made the trip to Sherwood Gardens by car from their Charles Village home to check on their bed of nasturtiums, which are beginning to sprout their first leaves.

Passing through the garden three years ago, watching neighbors water their plots and tend their flower beds, Paquet-Estes saw an opportunity to have a real garden of her own. "I thought, 'Wow - a chance to get my hands dirty,' " she says.

The project also has drawn two corporate contributors for whom gardening is a business. Beechfield Landscaping Inc. and Green Fields Nursery and Landscaping Co. tend plots.

Still, what the amateur gardeners seem to prize above masterful manicuring is the sense of community that comes from their summers taking care of Sherwood Gardens.

'Real social aspect'

"I've met more people through this than I've met through anything else," Barnett says. "It's got a real social aspect."

"It has made a lot of difference in the neighborhood," says Bettina Jenkins, who checks her plot and admires the others during a daily walk that takes her once around Sherwood Gardens. "Many more people go down to the gardens now than they used to, because there's something to see. ... It's a pulling-together of the neighborhood, and it really gives it a lot of spirit."