We’re finally finished building our custom raised garden bed, and today we’re sharing our design and construction process.
Let’s get right to the specifics! We built the base of the raised bed from 2 x 10 untreated cedar boards. Cedar is a great choice for raised garden bed construction. It’s both food-safe (since we’ll be eating things from this garden) and very weather/rot-resistant.
Our local Menards had a great selection of cedar lumber, and we were able to get a lot of the boards cut down to the lengths we needed (and to fit in our car for the ride home).
We designed the box base to be 4 feet wide by 6 feet long by 10 inches deep. It’s just wide enough to let us reach the plants in the center from the long sides, and the 10-inch depth will allow us to grow root crops like carrots, radishes and turnips.
John built the box outside on the site we’d chosen, and made sure it was level before attaching the sides together.
We also attached a layer of galvanized wire mesh and landscape fabric to the underside of the box. This will help keep out weeds, any existing plants or bulbs we might have missed, and even potential tunneling rodents. We poked small holes in the fabric for drainage, and John drove stakes into the ground at the corners and screwed them into the base once it was in place for stability.
So far, so good! But ultimately we needed our raised bed to be more protected from the neighborhood wildlife (which includes squirrels, rabbits, birds, and even the occasional raccoon). We love having visitors in our backyard, but not when they eat our homegrown produce.
So we designed a custom “roof” to sit permanently on top of the box base to keep out critters. The roof is basically a frame of thin cedar boards, with galvanized wire mesh covering the open spaces.
The idea is to maximize sunlight, rainfall, air circulation, and beneficial insect access (like pollinating bees), while minimizing intrusion from anything larger (like pesky rabbits). John built the roof to be 3 feet high at the “peak” to accommodate plants that can grow that tall, like bush peas, beans and broccoli.
To give us easy access to the inside of the garden bed for planting, watering and harvesting, John created doors for the long sides of the roof that hinge open from the top. These are also made from thin cedar boards, to minimize shadows from incoming sunlight.
Once the raised bed and roof were constructed (and before we permanently attached the doors), I created a custom soil mixture to fill the box base, following the formula for Mel’s Mix. As outlined in Square Foot Gardening, Mel’s Mix is a combination of equal parts blended compost, perlite or vermiculite, and peat moss.
First, I got several bags of compost from different sources (such as mushroom compost, humus, manure, leaf, etc.) and mixed those together. Then I raked together equal amounts of the compost, perlite, and peat moss on a large tarp in our backyard until it was well combined.
As I mixed the soil and added it in batches to the raised bed, John stapled the wire mesh to the frame and doors.
To minimize the metallic glare of the wire mesh, we spray-painted it matte black (except for the north side against the fence, which we left as bare metal to function as a trellis for pea vines). The black color helps the mesh visually disappear and absorb sunlight. After attaching the mesh, John attached the doors to the frame with galvanized hinges.
I also picked up a couple of basic 5-gallon buckets from the home improvement store to use as deep planting containers, for growing additional edibles that are too tall for the raised bed (like tomatoes). I painted them deep green to cover up their utilitarian appearance and help them blend into the garden, put some styrofoam pieces in the bottoms for drainage, and filled them with my soil mix.
I also refreshed some old metal tomato cages from our garage with a quick coat of spray paint. Since we’re trying to keep costs low with this project, this was an easy (and inexpensive) way to give a new look to existing containers and materials.
To get the most from our available space in the raised garden bed, I marked out specific planting areas with jute twine and garden staples. Since I’m not following a strict square-foot gardening layout, these are mostly temporary guidelines just to help me organize and plant seeds and starts.
And with that, our custom covered raised garden bed is finished!
Now that spring is officially upon us, it’s time to actually start planting. In our next post, we’ll share what we’re doing with our indoor seedlings and how we’re direct-sowing outside as well.