Bob Sauer built his garden wheelbarrow by wheelbarrow.

He hauled in dirt to improve the soil and to change the topography of the sloping site. He moved more than 70 pickup-truck loads of rocks, cobblestones and scrap granite to build walkways, steps, a terrace and most of the nine walls that define his sprawling Edina yard. And he lugged out a crumbling concrete sidewalk, diseased trees and scrubby brush.

In fact, Sauer has been schlepping -- and propagating and transplanting and deadheading -- for a good 20 years now. And still he's not done. But that doesn't seem to bother a man who takes the long view in his garden, literally and figuratively.

The centerpiece of the garden Sauer created, with the help of his longtime partner, Robert Zoller, is a large, parklike front lawn that offers a view from their hilltop house down to the custom-built rock wall that marks the boundary of their 1-acre property.

Sauer and Zoller use the sparsely planted front lawn as a place to entertain, hosting family reunions and birthday parties there. Sauer's great-nieces and -nephews climb on the statues the men commissioned for their garden and roll down the grassy hill.

"The kids play out here," said Sauer. "To them, it's a mountain."

To Sauer, it's a design element. Many gardeners pride themselves on converting grass to garden, leaving little or no lawn. But Sauer makes strategic use of it.

"I like grass," he said. "It sets off the garden, it sets off your plants. I don't like perennials and shrubs around the base of trees. It looks so busy. Trees should be able to stand on their own."

The trees do stand on their own, including several bird's nest spruce from Sauer's conifer collection and an ancient and daringly angled butternut. There is one flower bed in the front: a large daylily bed filled with more than 50 cultivars, including three that Sauer hybridized himself and officially registered with the American Hemerocallis Society.

Although he no longer hybridizes ("it takes an awful lot of time and patience"), he still spends plenty of time with the daylilies. "I'm a neat freak, so I'm always deadheading."

Daylilies aren't the only flowers that demand his attention. Sauer's private park gives way to a series of more intimate gardens once you round the house. There's a peony garden and a conifer garden that boasts unusual cultivars such as Japanese umbrella pine, Swiss stone pine, weeping Norway spruce and Alberta spruce, some of which he wraps in protective burlap for winter. "That's a two-day deal, wrapping shrubs in fall," he said.

He designed a terrace garden by planting moss roses, dianthus, pasque flower and California poppies in a grid of cobblestone. And he's planted so many hostas in the garden under the Schwedler maple that he's long forgotten just how many cultivars he has.

Driven by his love of a varied landscape, Sauer excavated part of the sloping back yard (that wheelbarrow again), and built rock walls to form what he refers to as his secret garden -- or his mosquito garden, when they're biting. There, under the shade of a magnolia tree, he planted Japanese painted ferns, European ginger and lady's mantle. To make the garden as tranquil as possible, he built a bench from granite slabs and he even started moss growing on the stones.

The gardens go on: a spring garden of bulbs and primroses, a holding garden for "problem plants," a Japanese fern garden. And they're all connected by the paths that Sauer built from cobblestones, pavers and granite slabs he salvaged.

The self-taught gardener also taught himself to build stone walls, including a long, low wall that runs the length of the driveway and a freestanding wall he built in honor of his father, who worked for a granite company for 45 years. "I guess rocks are part of my life," Sauer said.

Sauer, who's retired from a position with the federal government, said he considers his garden "mature," like himself. And although he's thinking about building a low wall to edge the poppies, he doesn't have plans for any more major excavations. But he said his garden is -- and always will be -- a work in progress.

"I'm happy with the garden now more than ever," he said. "But it's not going to stay the same. Things die, trees get big. A sun garden turns into a shade garden. You have to go along with it and be part of the change. A garden is never finished," he said. "We'll be finished before the garden is."

Connie Nelson • 612-673-7087