After growing up among steel mills near Dusseldorf, Germany, Juergen Mross felt very much at home when he moved to Pittsburgh in the 1970s. But he wasn't as comfortable in the 1950s red-brick Colonial he and his wife, Renate, bought in Edgeworth in 1986. It was large enough for the couple and their four sons, but it had a small entrance and lacked character.

Not anymore.

With the help of Gretchen Barlett of Barlett Design, the couple added a foyer and portico with six massive columns in front. Then, in 2006 and 2007, they had landscape architect Ed Werley of Werley Associates and landscape contractor Eichenlaub transform the grounds around the house. Now Mr. Mross feels at home.

"I fixed what I always thought was wrong with the house," he said.

The Mrosses' garden is one of six in Sewickley and Edgeworth that will be open today from 10 a.m. to 4 p.m. for A Midsummer's Day Garden Tour, sponsored by the Sewickley Civic Garden Council.

Although the house separates the front and back areas, the garden is unified by repetition and contrast, both of naturally mounding plants like azalea, spirea and itea and of curving formal hedges of sheared hornbeams and boxwood. The rows of tall hornbeams, in particular, give the front landscape a formal, European feel. Recently, Hilbish McGee Lighting Design added low-voltage lighting that highlights the hornbeams, facade and other features at night.

In the front and back, large uplights catch the huge old maples and pine trees that form the backdrop for the new landscaping and, in one sense, inspired it. After large limbs nearly struck the house during a storm, Mr. Mross decided it was time for a big change, starting with the elevations. Mr. Werley, who works with his son, John, said the front yard was raised 3 feet and a series of sandstone walls installed around a central curving staircase of carved limestone slabs.

Brick pavers were added near the street to create a dropoff area and are repeated in the walkways and a landing. There, a sculpture of upright logs cast in bronze by artist Peter Calaboyias is the center of a fountain. Originally on the side of the house, it was moved "for greater visual impact," Mr. Werley said. At night, the hornbeams also pack a visual punch, each with its own uplight.

"There's a lot going on there, but it's not bright. It's subtle," said Halbane Hilbish, principal owner of Hilbish McGee and a member of the International Association of Lighting Designers.

In the back, Mr. Hilbish subtly lit Japanese maples, weeping Camperdown elms and low sandstone walls topped by loose hedges of yew and blue holly and rows of spirea and cranberry bush viburnum. Three weeping cherries and other specimen trees were salvaged from an earlier redesign and reused.

Other older elements play parts in the new design. A new arched gate leads to "the treehouse," where the four Mross boys held countless sleepovers. They're now ages 30, 27, 25 and 18. The new curving stone walls bracket a new cedar garden house built by Vixen Hill, and new sheared boxwood hedges line the new conservatory. More 'Winter Gem' boxwood and a bay window frame a Japanese Stewartia that has been limbed up slightly to enhance the view of the garden. Around its base are Yak rhododendrons, fothergilla and 'Goldflame' spirea.

"The spirea has flowers and nice fall color -- a yellowish red," said Ryan Johnson, project administrator for Eichenlaub.

He said the hardest part of this project was access -- a road had to be cut from front to back -- and finding space to stockpile plants and materials. When it was finished, it won an Award for Landscape Excellence from the Pennsylvania Landscape and Nursery Association.

But the real measure of a project's success is whether it pleases the client. This one clearly does:

"There's always something blooming here," Mr. Mross said. "I never get tired of walking around my own house."