The interior of the box features a corrugated asphalt roofing panel (see SOURCES in PDF below) that enhances stability and water resistance and adds color to the project. All of the other parts are made of cedar, screwed and glued together to form a strong framework.
Use soil-less potting mix rather than planting soil or dirt from your yard for a container garden, recommends Kathy Childers, editor of Gardening How-To magazine. A typical mix is a blend of mineral rock, compost and peat moss, which makes it lightweight and well-draining yet able to retain moisture and nutrients.
Cedar is a weather-resistant wood, but because it can split easily, I recommend boring pilot holes before driving the 1-1/4-in. stainless steel screws (chosen because they do not stain the wood.) A countersink drill bit helps to hide the screwheads. For a strong, invisible joint, we used a Kreg jig to drill pocket holes.
Although it’s not required, using a Type 1 PVA glue, epoxy adhesive or polyurethane glue before you clamp and screw the boards together will ensure a strong bond that resists splitting. When using epoxy, be sure to wear gloves and a respirator and work in a well-ventilated area. Mix only the amount of glue that you can apply within the setting time. Use a fl at stick or disposable chip brush to apply the glue; then clamp the parts and drive the screws. Wipe away any excess glue before it dries.
Building the Planter
Following the cutting list dimensions (in PDF, below), measure and cut all of the cedar parts (A through K). We used a carpenter’s saw (photo A), but a circular saw or miter saw would speed up the process. All of the parts have 90-degree cuts, except for the top frames (F and G), which have 45-degree miter cuts.
Measure, mark and then cut the cedar boards to length. All of the cuts can be made with a carpenter’s saw or a power saw.
To create the decorative cutout on the four front/back panels (B), measure and mark the panel centers at 22-1/2 in. along one edge; then measure 3-1/2 in. on either side of the centerline and 1-1/2 in. from the edge of the board to form a triangle (photo B). Using a handsaw, carefully cut the reveal.
Cut a triangle from the center of each of the four panels that form the back and front of the planter.
Follow the step-by-step photos below to build the planter. When construction is complete, you can sand and finish the wood or leave it natural, depending on the look you desire. Place the planter on level ground in a spot that gets sufficient sunlight. Fill it with good-quality potting soil, plant vegetables or flowers and let nature do the rest.
Start by constructing the four legs. Clamp two leg parts (A) together at a right angle and drill pilot holes to prevent splitting. Glue, clamp and fasten the joints. (You can also use a pocket-hole jig for joinery throughout the project; learn more about pocket hole jigs here.)
Assemble each planter end, gluing and fastening two upper end panels (C) and one lower end panel (D) between two leg assemblies. Refer to the illustration for proper spacing between the panel pieces. Note the direction of the leg butt joints in the photo.
Lay an end-panel assembly on a flat surface; then glue and clamp the front and back panels (B) to the legs. Be sure that the triangle cutouts are facing the right direction to form the diamond-shape reveal and use a carpenter’s square to ensure a 90-degree joint. Add the second end panel in the same way.
Using glue, clamps and screws, fasten an inner spacer block (K) to the center of each lower end panel (D). Next, fasten the stretchers (E) to the ends of the spacer blocks. Secure the four outer spacer blocks (J) to the lower end panels on either side of the stretchers. The spacer blocks help to lock the stretchers in position.
With the stretchers and blocks in place, turn the planter upright and check that it is plumb and square. Fasten the two slat supports (I) to the lowest inside edges of the front/back panels (B). Attach the five slats (H) to the slat supports.
Fasten the top frames (F and G) to the top edges of the planter using glue and finishing nails as shown here. (If you prefer, you could use pocket holes and screws driven from the inside of the side panels.)
Following the cutting list dimensions, use a saw or sharp utility knife to cut the corrugated panels (L, M and N). Fasten the panels to the inside of the planter with brad nails or screws.
Drill 1/2-in. drainage holes in the “channels” of the bottom panel between the slats. To help retain the soil, staple landscape fabric to the inside of the planter. (Another approach is to use individual plant containers, which would allow you to easily swap out plants.)