How we built our raised beds

When we first decided to have a garden (when we bought the house in 1994), we thought that three 8-foot by 8-foot beds butted up against each other in an "L" shape seemed like a good idea. We built them of landscape timbers stacked three high, and filled with almost pure compost. We gardened in them for a few years loosely based on Mel Bartholomew's Square Foot Gardening (its specifics require significant tweaking to work in the Deep South where we are).

We learned several things from that experience, most notably that Jeff Ball was right in Jeff Ball's 60-Minute Vegetable Garden when he said to only make beds 3 to 4 foot wide. Also, the inside corner of the "L" interfered with drainage from our yard, the compost evaporated rapidly, and the landscape timbers didn't look very good after a few years (not to mention all the scraped legs we got from the rebar holding them in place).

Since our garden is in the front yard (southern exposure), it was important to have it look good. When we undertook to replace the old beds, we needed a new layout and new materials that we could keep attractive with a reasonable amount of maintenance. For visual interest and ease of following a crop rotation plan, we designed it as a parterre with an "exploded square" of four 8x4-foot beds in the shape of an "X" with a 4x4 foot bed in the middle. Four triangular beds fill in the sides of the "X" and are generally filled with wildflowers.

To avoid the problems of rotting and the possible toxicity of treated wood, we opted to use Trex, a composite lumber made of recycled plastic and wood fiber, to build the beds. Adapting the methods laid out in Jeff Ball's 60-Minute Vegetable Garden, we cut our lumber to size, and used two two-by-sixes, stacked, to make the 12" high sides. The boards are secured to each other and the ground by strapping 1 1/2" PVC to them, and pounding the end of the PVC into the ground. The PVC is on the inside of the finished beds, one pipe for every three linear feet of bed wall, and extends about 6 inches into the soil. Corners are secured with 90 degree angle brackets on the inside. Today, we would use the neat staked brackets that several companies sell for the corners.

Evaluation

The beds have held up perfectly well over the past five years. People often ask us what they are made out of. They also ask us what the PVC is for (they usually think it is for irrigation) -- since it is white, it stands out. We should have used gray to match the Trex (hindsight!).

The biggest mistake we made was in the width of the paths. We thought that we could make them one mower-width wide and leave them as grass, but getting the mower around the corners and through the occasional not-quite-a-full-mower-wide spaces has proven to be a pain, not to mention dodging escapees from the beds. This year, we gave up on grass walkways and mulched them heavily with leaves topped with pine needles.

Written by rj. Last updated 4 Feb 4 by sj.