My wife asked if I could build a planter box for the back of the house that was playful and just for us (and our toddler) to enjoy. A Mario brick or question mark block planter is not a completely original idea, however I found no builds that really brought the block set to life in three dimensions. So that was my goal for this project.
Step 1: Gather Materials
(1) 12" x 8' Cedar Board (box walls) https://www.homedepot.com/p/3-4-in-x-12-in-x-8-ft...
(1) 2" x 4" Kiln dried after treated (KDAT) ** (For the bricks)
(4) 2" x 2" x 42" Pressure treated yellow pine baluster https://www.homedepot.com/p/2-in-x-2-in-x-42-in-P...
(1) 6 ft Cedar fence board
(1) Red exterior paint (I used Rust-oleum's Colonial Red) https://www.homedepot.com/p/Rust-Oleum-Painter-s-T...
(1) Yellow exterior paint (I used Rust-oleum's Golden Sunset) https://www.homedepot.com/p/Rust-Oleum-Painter-s-T...
(1) Dark exterior paint for the base color (I used Rust-oleum's Metallic Oil Rubbed Bronze)
(2) Cans of spray on primer filler
(1) Can grey spray paint (optional to match legs to concrete)
(1) Roll on primer
150-220 (or similar) grit sandpaper
**KDAT may be hard to find and likely would require a special order. Some other options may include:
- Use regular pressure texted lumber but it must be dried before painting, which can take months.
- Use another cedar fence board, but it may be difficult to smooth and I've read it can bleed tannis which could effect a paint job.
- Use regular kiln dried lumber, the use a paintable treatment like Woodlife Classic, but you will have to use screws on each brick rather than glue.
- Use a much more expensive outdoor wood like the ones listed here https://www.woodworkerssource.com/shop/category/ou..
Power Tools / Equipment:
Router with roundover bit (ideally a router table)
3D Printer (not required if your able to cut the question mark by hand)
Miter saw (also not required since all cuts could be done view the table saw, but it helps)
Clamps (corner, regular and long)
Paint brushes and rollers
Step 2: Cut and Assemble the Planter Walls
See the cut diagram for all cut measurements.
Cut the four side walls from the single 12" (11.25" actual width) cedar board.
Next, cut the "Base Frame" from the 2 x 2 pressure treated yellow pine balusters. These cuts will need to be mitered at 45 degrees.
Finally cut the bottom boards from the cedar fence board.
Now use a piece of fence board as a guide to space the base frame from the bottom of the planter wall (see photo). This will ensure that when you attach the bottom it will sit flush. Also make sure the base frame pieces are centered on the walls. The longer pieces should be shorter than the side walls to account for the shorter sides being screwed on the inside. In my case one side of the cedar was smooth while the other was rough, so i made sure the face the smooth side outward to save me from having to sand it smooth.
Step 3: Assemble the Base Planter Box
I added some optional wood glue then clamped the walls together making a box. Then I pre-drilled 3 pilot holes in each corner before screwing them all together and removing the clamps. The joint is a simple butt joint with the shorter sides on the inside of the planter. The screws will be covered by the bricks so make sure they are flush with the wood or sunken a bit.
Next I flipped over the box to put the bottom boards in place. They often are a tight fit because of the imperfect nature of the fence boards edges. I suggest placing them so they leaning on each other (see photo) before pressing them down in to place. Next pre-drill and screw them down through the base frame. I was pretty liberal with the screws placing them about 4" apart.
Next drill drain holes at the bottom of the planter. I drilled a couple of 1/4" holes.
Finally I sanded the joints using a belt sander and 80 grit sand paper because my wood had some slight warp to it and you want the joints smooth for the "bricks" to wrap around (see photo).
Step 4: Cutting the Bricks
Rip the 2" x 4" so that each side is only 1/2" thick. In the initial photo the board was ripped directly in half. But I found that to be too thick so I re-ripped each half to shave it down to 1/2". With my 10" table saw I could not cut through in one pass, so I had to flip the board to complete the cut.
Once you have the 1/2" board, you can begin cutting the individual bricks.
- 18 Full bricks (3.5" x 5 11/32")
- 12 Side bricks (3.5" x 2.5")
But I'd cut a few extra in case you encounter flaws.
Once those are cut, it is really satisfying to do a test layout. The gap between bricks works out to be 3/8" (or .375"). But I ended up eye-balling the spacing for mine pretty easily.
Finally, miter a 45 degree cut from 6 of the full bricks and 6 of the side bricks. Make sure the longest side (which should be the rounded top side) is still the original length of the brick and you are only cutting away enough material to create the miter cut.
I once again placed the test layout with the new miter cuts in place and measured that the center square was right at 11.25"
Step 5: Finish Building the Bricks
To complete the bricks we first need to round all the hard edges left on the face using a router (ideally a router tables) so that all sides are rounded.
Next, I rested a belt sander on it's side and quickly smoothed all the top faces of the bricks using 240 grit sandpaper. This should take less than 10 seconds per brick.
After smoothing the bricks, you can glue together all mitered pieces and clamp them using corner clamps, although in my case I usually just did a single corner clamp and a basic clamp to ensure it fastened evenly. You will have 6 sets always matching a full brick with a side brick.
Once the corners are glued and dried, you can round the corners where the pieces meet and then do another test layout with your new wrap around bricks.
Step 6: Painting the Bricks
Nothing unexpected here... I Just used some primer filler to help build up a slightly smoother surface and fill any small grain texture. Then I LIGHTLY sanded each brick smooth by hand (again around 5 seconds per brick) but ensuring not to sand off the primer. Finally, I spray painted the bricks red using Rust-oleum's Colonial Red.
Step 7: Painting the Planter Box
First I lightly and quickly hand sanded the outside of the box with some 150 grit sandpaper just to rough up the smooth surface for painting.
Something I'd suggest doing differently, if you plan to glue the bricks, is to lay down pieces of painters tape behind where each brick will lay. Then once it's primed and painted you could peel off the tape to reveal raw wood in which to glue. For this reason it doesn't need to be the entire brick shape, just a section of the middle.
Then I applied some roll on primer. While that was drying I brushed on a coat of waterproofing sealer to the inside of the box. I'm not sure if this is necessary or would help to extend the life of the planter, but I figured it couldn't hurt.
Once primer was dried I rolled on my dark paint (Rust-oleum's Metallic Oil Rubbed Bronze) pretty half haphazardly as it will hardly be visible.
As you can see from my last picture, if you don't do the painters tape method and decide to use glue, you'd need to sand off portions of the paint behind each brick to give yourself a good wood to wood hold.
Step 8: Attaching the Bricks
Begin clamping and wood gluing bricks leaving them pressed 30 minutes to 1 hour. Once all the clamp-accessible bricks were glued I had to start improvising. But it only requires objects with a bit of weight and a flat surface.
An optional, but nice, touch was to paint the top edge of the box to feel like a continuation of the brick (This will be visible in future step photos because I forgot to photograph it at this stage).
Step 9: Creating the Question Block
The question mark board was designed in Tinkercad and will require a large printer capable of printing an 11.25" square. I have the popular CR-10 and it barely fit on the bed. There are 2 versions of the block background (FULL and THIN). This is because I saved on print time by printing a full version and using PVC trim as a spacer (view in next step). But if you prefer to print the full version as one piece you have that option.
Even though the block background was printed in yellow, it was not the yellow I wanted. So I decided to spray paint it using Rust-oleum's Golden Sunset.
First I suggest putting down SOME painters tape inside the question mark slot because we will be gluing it in place and plastic to plastic would be a better hold.
I had to again use primer filler which made what looked like a great print, look terrible. So once it dried I had to wet sand the primer using 220 grit sandpaper. Then once that dried I did it all over again (prime and wet sand) 2 more times.
Finally, once it was smooth I hit it with a decent coat of the Golden Sunset paint.
Step 10: Attaching the Question Block
This is an optional approach and I'm sure there are better ways but, as mentioned in the previous step, I had some 1/4" thick PVC trim lying around so I decided the print the question mark block thinner (to save print time) then paint and screw in the trim directly to the box. This way I could just super glue the question mark to the trim leaving you with a screw free finish. I also super glued the question mark itself at the same time. If you do not use the trim you could either screw directly through the question block or find a good adhesive for both wood and plastic.
Step 11: Cutting and Attaching Legs
Using the same 2" x 2" pine baluster from previous steps, I spray painted some grey I had lying around to blend more with my concrete. I cut the legs around 3" tall, but it all depends on preference or window height.
To attach the legs I used wood glue, but only because of the leg length. If they had been shorter, I certainly would have opted to use screws instead. You'll need fairly long clamps (15" or longer).
Step 12: Print the Pipe
The pipe was also created in Tinkercad and 3D printed on the same CR-10 as the question mark. But it should fit on medium sized printers also. I suppose this could easily be created with a PVC pipe and fitting then painted, but I have a printer and green filament, so why not use them.
Step 13: Finished Product
Before adding flowers I stapled in a trash bag as a liner and poked drainage holes. Can't say if this is entirely necessary, but it seemed like another way to extend the life of the pot. After that I filled the pot with dirt and got to planting. I was pretty happy to find a red to yellow daisy that works as a Fire Flower.
I hope this project is helpful for any modern or retro gaming enthusiasts that would like to add some flair to their landscape. Thanks for reading!
First Prize in the