According to area experts, homeowners should view a pergola as both a piece of art and a shade provider.

"It gives a garden character and definition," says Jeff Hershberger, a landscape designer at David J. Frank Landscaping in Germantown. "It also gives structure or scale to the garden."

A pergola consists of columns that support a slated wood roof. Placement of the beams is critical and determines how much light is allowed through. In addition to adding a special architectural element to the yard, it creates some cool shadowing too, says Hershberger.

Pergolas can attach to a home, outdoor fireplace or cabana house. People also add "vining," which grows up the sides and over the top of the structure. In Wisconsin, pergolas are usually made out of cedar, which Hershberger says is more resistant to decay.

Michael Patek, owner of The Cottage Gardener in Sussex, sees two main reasons for having a pergola: It produces an element of enclosure and it provides some shade.

"People are looking to their outdoor space for solving a sun problem," says Patek,­ who custom designs pergolas for customers. "They are aware there are alternatives to waiting for a tree to grow."

His favorite thing about a pergola? "The intimacy," he says. "It can do that very quickly in a wide open space." M