How to Make a DIY Planter Box on Wheels
"The only challenge I faced was attaching the axle to the wood legs, but this was solved with a method my dad and grandpa used while building go-carts during my dad’s childhood: large staples hammered into the wood around the axle."
Materials
For the sixth year, we’re heading to the Northwest Flower and Garden Festival. We're excited to bring you more fun projects at the Dunn DIY booth to help you move forward in your DIY journey, so make sure to stop by booth 707 to say hello! The show runs Feb. 26 through March 1.
Do you ever have those moments when you’re convinced something is going to work—even when you run into setbacks—and at the very last minute you realize you need to change your whole game plan? This rolling planter project was one of those moments for me. I’ve been running Dunn DIY for almost six years now, and (for the most part) I think I’ve got the creative process down. I’ve learned how to think up something in my head and translate it smoothly into reality. Even the setbacks and the road bumps along the way have become an expected part of the process.
The trouble spots I was expecting in this project related to the rolling part of the planter. Although I’ve worked with casters before, I’ve never worked with inflatable wheels that are attached to an axle that's secured to the wood part of a structure. Any time I’m handling something new, I get a little nervous. I feel less confident. And, usually, I bring in a second opinion. For this project, I was prepared to hit roadblocks, and I had time prepared for working those out. But then, things went smoothly. I found the exact wheels I needed, and the axle and axle nuts turned out to be products we carry at Dunn Lumber. It was as simple as inflating the wheels with a bike pump, cutting the axle down to size with a hacksaw, and hammering the axle nuts on the ends. Easy as can be. The only challenge I faced was attaching the axle to the wood legs, but this was solved with a method my dad and grandpa used while building go-carts during my dad’s childhood: large staples hammered into the wood around the axle.
Everything that was supposed to be complicated went smoothly. It was turning out to be an easy project. Well, it would have been, except the easy part turned out to be the complicated part. I was set on this planter having side walls that angled out, and I was determined to have the corners mitered because I thought that would look best with the brackets I was using. I was also determined to have a reveal between the top and bottom parts of the walls. (That meant another layer of wood I needed to work into the sides.) But nothing I did worked. My math failed me over and over again. I realized if the side walls were angled, I needed to cut the base sides at an angle, as well. And figuring out the varying dimensions of the bottom half of the wall when it was cut at an angle was a nightmare. I cut, recut, adjusted, and recut again. I worked late into the night before I finally worked out all the math and details. Then, as I was loading everything into my car for the morning’s shoot, I had a horrible realization: This design was too heavy, and it wasn’t even fully built (or filled with soil yet). I knew I needed to change it. Note: the final product was still pretty heavy; I think it's unavoidable when you're dealing with so much soil. If weight is a concern to you, I recommend scaling down the project.
So, at 11 p.m. the night before, I came up with a new design. I loaded up enough extra lumber to recut some pieces, and I hoped this time I could flawlessly translate what was in my head into reality. And though I wouldn’t necessarily say it went “flawlessly,” it went about as well as I could have hoped. Here is the new plan for this project, changed overnight. Overall, there were only a few things I would have done differently, but (as usual) you get to learn from my mistakes, and I’ll let you know all of those details throughout this tutorial. Let’s get started!
Step 1: Cut and assemble planter base
For this project, I made cuts with a miter saw (a chop saw that pivots to cut at an angle), but you can also make cuts with a Speed Square and a handsaw or a circular saw.
First, cut a one-by-eight piece of lumber into two 46 1/2” lengths. Then, cut the two-by-twos into two 46 1/2” lengths and three 12 1/8” lengths. Position the 46 1/2” two-by-two pieces along the bottom of the one-by-eights, flush with one side. Secure the pieces together with 1 1/2” screws driven through the top of the one-by-eights.
Place the pair of one-by-eights and two-by-twos next to each other with the two-by-twos on the outside. Position the 12 1/8” two-by-twos in between the longer two-by-twos at both ends and in the middle. Secure in the same manner. There should be a 1/4” gap in between the one-by-eights for drainage.
Step 2: Cut and assemble first tier of planter walls
In this step, you’ll measure around the outside of the base and cut the lengths of board accordingly to make sure the first tier of the planter walls fits around your base. This was the first step where I ran into an unforeseen problem. I cut the walls of the planter with mitered cuts so the black brackets on the corners would look smooth and sleek. What I didn’t anticipate was this: The brackets have a curved corner on the inside—rather than a sharp angle—and because the wood makes a sharp 90° angle, the bracket pushed the two pieces of wood away from each other and created a gap. This was not at all what I was hoping for. It isn’t necessarily a problem beyond aesthetics (though I do have some concerns with the soil putting pressure on that seam), but it was enough of a problem for me.
I continued to work on this problem, and I came up with a few different solutions (you may notice my final shots are different from the photo steps because I ended up implementing one of these solutions). One option involves dropping the mitered corners. If you’re working with straight cut edges, the brackets don’t create a gap. Instead, the two pieces are inset, so they’re not completely flush but the seam is still tight. With this technique, I was surprised by how much I liked the look of the brackets without the mitered corners.
Alternatively, if you want to keep the mitered cuts, the solution involves securing the wood together before adding the brackets. This can be done with nails, screws, or glue. I tried a fast-drying wood glue to no avail, so make sure you set aside enough time for drying if you decide to go that route. Using fasteners like screws or nails is a great option, especially if you position them so they’re ultimately covered by the brackets. A nail gun would make this step quick and easy, and I recommend using glue with any of the above techniques because it will keep the seams tight and stop the soil from sneaking out.
Now, let’s get back to the steps.
For absolute precision, I like to measure each side of the base separately and cut my one-by-eights accordingly. If you’re making mitered cuts, you’ll match the measurement of the base to the inside face of the mitered piece. If you’re making straight cuts, make sure that two of the sides are long enough to overlap the other sides. Either way, the more precise you are with your cuts, the cleaner the finished product will be.
Once your pieces are cut, you can secure them to the base of the planter. This is done by arranging each piece around the base and securing with glue and screws (or nails). The wall pieces can then be attached to each other in the same manner.
Next, place the bottom brackets around the corners 3/4” up from the base. If you’re making straight cuts, make sure the bracket is positioned so that one of the screws doesn’t end up in the seam between the two pieces of wood. For mitered cuts, the brackets can be arranged in whatever way looks most aesthetically pleasing to you. As much as I try to avoid pre-drilling whenever possible, I found pre-drilling made things a lot smoother because of the thickness of these screws.
Step 3: Add one-by-two supports
Next, cut and add one-by-two supports at the corners and in the middle of the long sides. These supports are there to add extra substance for the bracket screws to bite into. They should reach to the top of the walls (or just about) so the top brackets can be secured into them. Make sure the faces of the one-by-two lines match up with the longer side of the corner brackets.
Temporarily secure the corner one-by-twos in place with screws or nails and add the top brackets for this tier of the wall. Place these brackets 3/4” from the top of the one-by-eights. Secure the middle one-by-twos with a couple of 1 1/4" screws.
Step 4: Assemble top tier of planter walls
This step essentially repeats the steps for the first tier of walls. Cut the one-by-eights to length and secure in place on top of the first tier. For added stability, toenail (drive in at an angle) the screws or nails to connect the two tiers together and add some glue. This will help make sure the soil stays inside the planter. Secure the middle one-by-two supports to the top tier just like you did the bottom tier.
Step 5: Build planter legs
There are two sets of legs on this planter: an angled end and a straight end. Both are comprised of two two-by-four legs with a one-by-four crosspiece at the top. For the straight end, cut two 12 1/2” lengths out of the two-by-four and one 15 1/2” length from the one-by-four. For the angled end, cut two 21” lengths out of the two-by-four with parallel 16° angles at both ends. Cut one length of one-by-four with opposing 16° angles. The shorter side of the board (the top side) should measure 15 1/2”. Assemble the two ends by positioning the one-by-four crosspieces at the tops of the two-by-four legs. Secure one-by-fours to the legs with a couple of 1 1/2” screws.
Next, cut two two-by-four brace pieces to 42 1/4” with parallel 10° angles at each end. These long brace pieces will connect the two pairs of legs. Line up the brace pieces with the bottom of the straight legs so that the one-by-four crosspiece is on the other side of the legs as the brace and the angle of the brace is sloping down toward the legs. Secure the pieces together through the legs with 3” screws.
Now, position the angled legs at one end of the planter bed base so that the one-by-four is facing out and lines up with the end of the planter. Secure legs firmly in place with two of the corner brackets.
Once these legs are attached to the planter bed, it’s time to fit in the other legs with the attached braces. These legs should be positioned opposite the first pair of legs, with the braces lined up approximately with the top of the angled legs. Secure the angled legs to the brace first, and then secure the straight legs to the planter bed base in the same manner as the angled legs.
For added stability, you can flip the planter right side up and drive a few long screws through the base of the bed into the tops of the legs.
Step 6: Add wheels
Begin attaching the wheels by hammering an axle nut onto one end of the axle. Slide one of the wheels onto the axle, followed by a stack of washers (I used 10) and the second wheel. Position the axle on the bottom of the straight legs with half of the washers on the outside of one leg and half on the outside of the other. The washers are there to alleviate friction so the wheels can spin freely. They also create a gap between the wheel and leg as an added buffer. I used washers, but you could also use a bit of copper or PVC pipe to accomplish this same task.
With the axle and wheels positioned on the legs, take the remaining axle nut and see exactly how much axle you’ll need to secure it in place. Be a little liberal so you don’t end up with an axle that’s too short. Mark with a pen. Remove both wheels and all of the washers from the axle and clamp it down on your work surface. Cut the axle to length with a hacksaw.
Once the axle is cut to size, slide the first wheel back on, followed by the washers, and then the second wheel. Hammer the axle nut onto the cut end. When you’ve ensured that it still fits on the legs, grab some staples and hammer them into the ends of the legs around the axle. We used two staples per leg. Remember, the wheels are supposed to turn around the axle—the axle itself isn’t supposed to turn (although it isn’t the end of the world if it does)—so hammer in those staples nice and firmly.
I got the idea for using staples to hold the axle in place from my dad. This was a technique he and his dad used growing up to build go-carts. The beauty of it is definitely in the simplicity. Once the planter (or go-cart) is right side up, the main pressure on the axle is a vertical pressure, which means the staples are just there to keep the axle from rolling out from under the legs.
Step 7: Attach handle to rolling planter
Adding a handle is totally optional, but I like the effect it has. We used this large, black handle that coordinated with the corner brackets. Unfortunately, the screws that came with this handle were longer than the walls of the planter and a little too thick to easily shorten with a pair of cutting pliers. The solution was adding a scrap piece of cedar to the inside of the planter for the screws to bite into.
Step 8: Finish
The final step of this project is to finish it. How is totally up to you! I love the warm tone that fresh cedar has, so I always like to add a semi-transparent coat of Penofin or Sikkens stain. If you’re not into that, you can leave your planter as-is and let it weather naturally, or apply LifeTime Wood Treatment. This one-time treatment jump-starts the weathering process and continues to provide protection over the full life of the wood. It will leave your planter with a nice silver- or olive-toned wood. Of course, if you’re going to be planting vegetables in this planter, read your labels to make sure the finish is compatible with edible plants.
Now that you’ve got a planter to house your favorite flowers or veggies, continue personalizing your yard by making your very own grill station, patio cooler stand, or vertical planter.
