In “The Garden Puzzle,” by the San Francisco design firm Organic Mechanics, Shepherd cut multihued Connecticut bluestone into precise-edged puzzle pieces that snuggled together to form the garden’s thematic floor. Here and there, a puzzle piece was “missing,” only to be filled in with tiny ground cover plants, tumbled glass or colored rock.

In “A Jewel Box Garden,” Shepherd fashioned the random-pattern floor of bluestone for designer Marcia Bloom of Menlo Park and landscaper Kevin Burns of Burlingame. He cut the intricate logo of the California Landscape Contractors Association display that included a slate maple leaf inset flush into a small sea of wavy-cut stone.

In “A Gesture of Balance,” by San Francisco designer Ric Lopez of ModernPast, Shepherd cut a round mandala with a floral motif of several types of stone that created a lovely focal point. The piece had the look of something laboriously cut and painstakingly fitted together. Instead, it was designed on a computer, cut in Shepherd’s small San Carlos workshop and quickly assembled at the Cow Palace.

Shepherd, a landscape contractor, developed his innovative approach after years of installing hardscape the traditional way on residential and commercial jobs. He calls his business Current Cutting Technology.

“I thought there must be a better way than cutting stone on site with a wet saw,” says Shepherd, 36. “There’s noise and dust and mess, and it takes forever.”

The technology Shepherd is using is more commonly used for cutting steel in automobile and airplane manufacturing.

The puzzle pieces cut by Shepherd also got the attention of San Francisco resident JoLynne Lockley. She bought the garden floor right off the floor of the show to install in her landscape at home.