Concrete is all around us, on streets, sidewalks and building foundations, so much so that we often overlook it as a decorative material...

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Concrete is all around us, on streets, sidewalks and building foundations, so much so that we often overlook it as a decorative material for our gardens. With attention to detail, concrete can enhance our outdoor spaces.

It can be used to define seating areas, guide visitors through parts of the garden and provide a backdrop for plantings.

The basics

Concrete is a mixture of Portland cement, sand and gravel. You can mix your own concrete with these materials, or buy bags of dry premixed concrete. Add water according to package directions, and mix it in a wheelbarrow or mixing pan. If you need a truckload of concrete, call a concrete supplier.

To find a concrete contractor, check ConcreteNetwork.com for a referral service or contact a ready-mix concrete delivery company.

Picking a surface

Patios and driveways are the usual concrete projects in landscapes. These often cover a large area, so consider the appearance carefully.

You can choose a smooth finish or a broom finish with a brushed texture. Adding a band of smooth concrete around an area of rougher texture can add interest to what might otherwise look plain. Bands of stone or brick also can divide larger areas of concrete to add character, and you could repeat the same stone or brick used in other places to tie the design together.

Another concrete surface choice is exposed aggregate with a pebble texture. To create it, the top layer of the concrete is sprayed with a chemical to retard hardening. When the concrete underneath has set up, the surface is washed so the pebbles in the concrete mixture are exposed.

Alternatively, pebbles can be seeded into the top of the wet concrete. Exposed aggregate can look dated since it has been used often in the past. To create a fresh look, choose pebbles in new and updated colors and sizes. You will probably want to work with a concrete professional.

Adding interest

Concrete can be colored by adding pigment to the concrete mix, or acid stains can be applied to the surface after it is set. Acid stains become an integral part of the concrete and will not wear off, giving a richly patterned effect when they react chemically with the variations in the concrete surface.

Stamped concrete is another way to add interest. The top surface is worked with tools to make a pattern that resembles stone or brick or just to give it a pleasing texture. Stamped concrete is less expensive than using the actual materials it is meant to look like. Stamped concrete is best left to professionals.

A concrete contractor can cover old concrete with a new thin layer to make a worn patio look new, or the surface can be stenciled with patterns and colors.

Stepping stones and walls

Another way to use concrete in the garden is with precast pavers. Buy them at a building supply center or at a stone yard. Use them for paths or patios. Some look like brick, others like cobblestones. Installation is within the skills of many homeowners. Lay them on a base made up of 4 inches of compacted crushed rock topped with 1 inch or so of sand.

Larger concrete pavers make good stepping stones for a casual path. Square pavers, 18 inches on each side, make an easy-to-lay path. Set the pavers about 6 inches apart, and plant ground cover between them. Stepping stones can also be cast in place. Use a plastic mold that casts a half dozen pavers at a time in an interlocking pattern, and then repeat along the length of the path. You could also make your own forms from 2x4s and draw patterns in the wet concrete.

Concrete walls can look rather utilitarian in a garden, but sometimes simple is best. They can be dressed up with a wash of paint to add color, or covered with plants. Draping plants such as bearberry cotoneaster (Cotoneaster dammeri) or kinnikinnick (Arctostaphylos uva-ursi) will fall over from the top, and self-clinging climbers such as Virginia creeper (Parthenocissus quinquefolia) will reach up from the ground.

Concrete is an inexpensive way to create hard surfaces in your garden. Give it a personal touch, and a plain material can be made out of the ordinary.

Phil Wood has a degree in landscape architecture and designs and builds gardens. Send questions to thegardendesigner@seattletimes.com. Sorry, no personal replies.