Raised Planting Beds

Sacramento Valley residents Borg and Joyce Halle have a beautiful property with plenty of space around their home for flowers, vegetables and herbs. The Halles like the idea of filling in some areas with raised beds for convenience but don't want the rudimentary look of typical planting beds, which are usually kept out of sight in the backyard.

To create raised beds that provide form as well as function, landscape architect David Yakish designs wedge-shaped beds that feature a clean, polished look and seating benches around the top. He also creates a layout that angles the beds slightly, giving them the appearance of radiating outward from the kitchen window. Ground-level beds planted with some of the same varieties used in the raised beds will further unify the structures with the landscape, along with tidy pathways between the beds, which will also enhance the polished look.

Yakish explains that the beds he and his crew will construct for the Halles are a practical project for most gardeners because they involve just a bit of hole-digging , hauling and sawing over the course of one weekend. On a difficulty scale of 1 to 5 (with 5 being the hardest), he rates the project a 2 and estimates that the total cost for materials, plants and supplies is around $700 (the job would cost about $3,800 if hired out).

To begin, the crew stakes out the area to mark the corners of the beds, then runs a string outline to mark the beds' perimeters. Because these beds are wedge shaped, the wider end measures about 40 inches, and the narrow end--which is closer to the kitchen window--measures about 24 inches; the length of the beds is roughly eight feet.

Next, the crew digs holes 12 inches deep for the posts, which are set in place with ready-mixed concrete. The 4x4 posts are cut to three-foot lengths, with one foot anchored in the ground for stability and two feet above ground to provide support for the framework. As the posts are set in place about four feet apart, they're repeatedly checked with a level to ensure that they're plumb .

After waiting 24 hours for the concrete to set, the crew lays lengths of PVC pipe in trenches for the beds' irrigation system. Crew members bury the pipe beneath the soil, then install separate valves for each bed so the amount of water can be tailored to each one. (Yakish recommends grouping plants with the same water requirements in the same bed to simplify the watering process.)

With the irrigation pipes in place, the crew builds the frames of the raised beds: 2" x 12" lengths of redwood are turned on edge and nailed to the posts with 3 1/2-inch brass-coated deck screws. (Yakish advises drilling pilot holes for the screws to avoid knocking the posts out of place when securing the framework; for this reason, he also avoids using nails.)

As each bed is constructed--all in the same manner--the 2" x 12 " framing boards are leveled, then stacked one on top of the other. When the framing is complete, each side of the bed consists of two boards, for a total height of two feet all around.

Step Two: Building Benches and Adding Plants

Before the beds are capped with the flat redwood planks that will form benches, the framework is filled with planting mix, which will provide the new plants with the perfect balance of compost, top soil and sand. (When the beds are half full, the crew lays the remaining pipes for the irrigation system on top of the soil, then fills the beds to the top. The professional irrigation system used here features emitters, but a standard drip system could also be used.)

Next, project coordinator Colton Chaney joins the crew to add the high-quality redwood 2" x 6" boards that will form the benches on top of the framework. Chaney recommends using wide boards to ensure comfortable seating, and notes that a 2" x 6" or wider board makes the best choice for benches.

Chaney wants to miter the ends of the planks where they meet at the corners of the beds--which aren't square but trapezoidal--so he lays the boards on top of the framework in their exact positions, then marks the angled cuts where boards will meet. Once he marks the ends, he cuts along the guidelines, lays each board back in place and secures it to the top of the framing with screws. (Using screws is preferable here, as earlier, to prevent knocking the structures out of alignment.)

Once the seating benches are in place, Yakish returns to plant the beds with a variety of flowers, herbs and other colorful plants. In the adjacent ground-level beds he uses more colorful foliage to "dress up" the raised beds and integrate them into the landscape.

The following plants are featured:

• Pennisetum setaceum, Zones 9-10
• Purple coneflower (Echinacea purpurea 'Magnus'), Zones 3-9
• Guara lindheimeri, Zones 6-9
• Penstemon 'Chester Scarlet', Zones 6-9
• Lamb's ears (Stachys byzantina), Zones 4-8
• Rosemary (Rosmarinus officinalis), Zones 8-10

Step Three: Putting in Pathways

With the raised beds built and planted, project coordinator Colton Chaney returns to create paths between them. The refined style of these wedge-shaped beds will be substantially enhanced by the manicured appearance of the pathways.

Chaney first digs out the areas to a depth of three inches to coincide with the existing sidewalk (the walkway runs perpendicular to the pathways, along the front of the beds). As he digs, Chaney keeps the ground fairly level but creates a slight tilt to one side that will help the areas drain.

After he finishes digging, Chaney lays header boards along the sides of the pathways. These are held in place with wooden stakes, which are nailed to the header boards with deck screws. Then Chaney fills in around the header boards with dirt.

Finally, Chaney fills the areas with decomposed (crushed) granite, which he spreads over the surface with a rake, creating a slight peak along the center. This technique, which Chaney refers to as "crowning," is designed to facilitate drainage. Then he presses the granite in place by repeatedly stamping the paths, taking care not to flatten the crowned contour. (He explains that although many people use tampers to compact crushed rock, foot power works just as well.)

Step Four: Project Review

With a variety of flowers and herbs filling both the raised and ground-level beds--and neatly filled pathways that provide easy access to the plants--the Halles are all set to enjoy the bounty of their handsome and convenient new garden.