Outdoor Rooms : Arbors: They blend with nature in connecting areas of a yard or defining a garden path. They’ve been providing rustic charm since days of the Roman Empire.

When G.R. (Gep) Durenberger opens his bedroom window, his eyes fall on a vine-covered arbor. “It catches your attention and creates a calming atmosphere in the garden,” says the San Juan Capistrano resident, who maintains two arbors in his back yard.

Used widely during the Roman Empire, arbors contribute a certain charm to any garden. Often covered with flowering vines, these vertical structures provide a shady retreat from summer sun, creating, in essence, “outdoor rooms.” Other free-standing arbors can be arched and have gates, seating or swings.

“Arbors are rustic in nature and aren’t built as an addition to a house, but are a part of the outdoor ‘home,’ ” says Jeffrey Garton, owner of Paradise Designs in Dana Point. “Arbors blend with nature. They are sometimes built with natural materials such as tree limbs and branches.”

Arbors often are used like doorways to create a transition from one place to another. “They connect areas of a yard,” Garton says. “For instance, (a person) may be in a courtyard, then pass through an arbor into a rose or vegetable garden.”

They also define a garden path. Durenberger’s arbors form a “hallway.” When people leave the “parking court,” they pass through his first arbor, follow a path to the second arbor and wander through it to a guest house.

Arbors are covered with vine-like plants that easily attach themselves and grow seemingly without limits. “All the plants in the vine family grow well on arbors, such as ivy, wisteria, Ficus pumila and cape honeysuckle,” says Nick Federoff, co-owner of A.N.B. Industries in Whittier and a horticultural instructor at Orange Coast and Golden West colleges.

Because of their similarities, many people confuse an arbor with its modern cousin, the trellis.

“Instead of being independent structures, trellises are often attached to something,” Garton says. “They are used as facades and to grow fruits and vegetables on. Some people construct them against a wall to soften it. They also use trellises as screens for such necessary, but unattractive equipment as air-conditioning units. Others are covered with flowers such as roses and used as attention-getting backdrops.”

Trellises often take center stage in Southern California gardens because of limited space. “Many people have cigar box-size back and front yards that often don’t have room for large structures such as arbors,” Federoff says. “But they do have space for trellises.”

Trellises come in myriad shapes and sizes. “There are fan-shaped, round, horizontal and vertical ones,” Federoff says. “Those that are used as screens have latticework in them. You can even create one out of wire that will force a plant to grow across a wall.”

Marie Bouse of Santa Ana has a variety of trellises in her yard, which she uses to support fruit trees and vegetable plants. Two kiwi plants grow on a trellis that goes up the sides of her garage and across the top. In front of her dining room window is another trellis, which holds a grape vine. On summer days, she can see clusters of hanging grapes outside her window.

Bouse, who grows much of the produce she eats, has trellises in her vegetable garden that she constructs out of metal conduit pipe. “They are free standing,” she says. “I started using them because they save space by forcing plants to grow upwards.”

Trellises also add beauty to her yard. “It is very attractive and enticing to see vegetables such as tomatoes hanging at eye level, instead of being buried under green foliage,” she says. “It can add a colorful display to your garden. The fruits and vegetables are also more healthy because they stay dry and are less likely to attract pests.”

By attaching wire to them, fences and walls can have a trellis look. Bouse has grown cucumbers, tomatoes, short varieties of squash, melons, mini-pumpkins and peas on her wire-wall trellises.

“Unlike arbors, which demand viny plants that have height, you can grow just about any (small) plant on a trellis,” says Federoff. “Dwarf lemons and oranges, ornamental pears, prostrate growing junipers and climbing roses all do very nicely. In shadier areas, gardenias and camellias grow very well on trellises.”

Gardeners should avoid planting vine-type plants on trellises unless they want to prune them frequently.

“The plants growing on a trellis are confined to that structure,” explains Garton. “Once a plant begins to leave the trellis, either you continue to trim it, or attach it to something else, such as a wall or fence. After a time, the trellis may become useless.”

Both arbors and trellises need directional training and pruning, which varies depending on the type of plant.

“With the vinier plants, you often want to take a stray vine, bend it over and clip it to a branch that is traveling in the direction you want it to go,” Federoff says.

This can be done with garden stretch tie or clothespins. If you’ve attached a clothespin, remove it when the plant begins to grow in the right direction.

If a vine or branch is wayward and there seems to be no hope of redirecting it, cut it with hand pruners. “Prune at a 45-degree angle a quarter of an inch above a bud because that will force new growth,” Federoff says. “Make sure the bud you are cutting above is facing in the direction you want the new foliage to grow.”

You can purchase trellises at nurseries and home supply stores. “Before you buy one, consider how big the plant is going to get and where it will be placed in the yard,” Federoff says. “You can even buy a plant and trellis together, which the nursery has already started training.”

Because of their size, arbors are generally not sold already constructed. However, homeowners can buy project plans or prefabricated units through the mail.

Better Homes and Gardens Shopping Service offers a selection of arbor drawings and instructions as well as a prefabricated unit. Kinsman Co. in Point Pleasant, Pa., also offers arbor kits. Other mail order companies can be found in gardening magazines.

You may prefer a custom-built arbor or trellis.

“The nice thing about custom- building trellises and arbors is that you can create your own patterns and designs,” Garton says. “For instance, the typical latticework in a trellis is set at 90-degree angles; you can place them at whatever angle you want.”

The type of wood you use to build an arbor or trellis is important. Redwood, for example, is both rot and termite resistant, Federoff says. “Under normal conditions, the life expectancy of a structure made with (redwood) is 30 to 50 years, compared to something that is built with untreated or less hardy wood, which could rot or be eaten by termites in about three years.

“When building a trellis or arbor, study patterns and designs found in garden books or magazines, or take a good look at trellises and arbors that are already made,” Federoff says. “Then let your imagination run wild as you construct your own.”