Build a square planter box from cedar

Our front porch was very sad. It had no design element… Do you have this problem? My goal this year was to add some elements to this space. I know that I finally did this right before winter but now next year I will be able to enjoy the planter box! Here is the planter box I built.

What do you think? The best part was that this is one you can DIY because it’s on the easier side! How about I share how to build your own planter box?

HOW TO BUILD A SQUARE PLANTER BOX

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CUTTING THE WOOD:

The first thing that needs to be done after purchasing the supplies is cutting the wood. Here are what lengths and how many you will need for a 14″ planter box.

16 – 16.5 inches 2×4 (sides)
4 – 3.75 inches 2×4 (legs)
2 – 15 inches 2×4 (bottom)
2 – 7.5 inches 2×4 (bottom)

ADDING KREG JIG POCKETS:

Now add pockets to the 2×4’s to be able to attach the wood together. Lay the 16.5 inch 2×4’s on a flat surface, grouping them in fours. These will be your sides. I did label each side and where the board was (1, 2, 3, and 4).

Next on the top and third board from the top, add two pockets on the left side. For the second and fourth board, add two pockets to the right side. Then for the second, third, and fourth boards; add 2 pockets to each end (about 2-3 inch away) of the long top side. All the pockets will look something like this. PLEASE NOTE: Picture is upside down!

Do this for all the sides.

Next, add 2 pockets to the top of the legs.

After adding 2 pockets to the 15-inch board along the long side. Then add 2 pockets to each end of the 7.5-inch board (4 together for each board). Here is a diagram of where all the pockets should go for each board.

ASSEMBLE SIDES:

To assemble the sides together, you will need two 16 inch clamps or a wall with some strap boards. I used a wall and it worked great!

Starting with side ONE, place the top 2×4 along the wall (1st). On the side of this board that has the pockets, place the SECOND side top board (1st) next to this piece. Use the scrap boards along the sides (see picture below). Then place the 2nd board from side ONE, next to the first board. The pockets along the length of this board will face the 1st board. On the side of the 2nd board with pockets, place side FOUR 2nd board next to the other piece (like before but another side). Continue this until you have all 4 boards in place. Will look like this.

Then use the 2.5-inch screws to attach just this side (side ONE) together, not the sides yet. Do this for all sides.

Once all the sides are assembled it’s time to create a box. Place side ONE on the ground and place side TWO into the gaps (have side TWO against the wall). Attach the side together with the 2.5-inch screws.

Continue turning and adding sides until all the sides are added. Make sure to use very pocket!

ATTACH THE SUPPORT:

Now to attach the support to hold the square plastic planter inside the wooden box. The planter I purchased is larger at the top than at the bottom, so I need additional support at the bottom. With the wooden box upside down on a level surface, I place the plastic planter inside the box. Then I took the 15-inch 2×4 board and marked where it needed to be attached by laying it across the planter. I wanted the plastic planter 1/4 inch lower than the wooden box, so I measured the distance and took off a 1/4 inch. My distance came out to 1.25 inches. I then marked one side (on the inside) at this distance. Then I attached the 15-inch board to that side with 2.5-inch screws. I did this again on the opposite side.

Then I attached the 7.5-inch boards inside those two boards but about 2-3 inches away from the sides. Looked like this.

ADD LEGS:

Now you should have a box, let’s add the legs with the box upside down. Pick a side of the box that you want to be the front. Make sure the bottom is level; if not use a sander to level (you don’t want wobbly legs). Then attach two legs on that side with the pockets facing the inside of the box. After attaching the other 2 legs to the opposite side the same way. SIDE NOTE: Picture below the legs are facing different directions, I decided I liked the look better of them all facing the same way.  

FINISHING TOUCHES:

If you want to chance not waterproofing the wood, your box would now be complete. But if you want it to last, stain/waterproof the wood now. I used Ready Seal in Natural Cedar, the same stuff we used on our fence and mailbox post.

Another thing you can do is add pocket plugs into the pockets (I would suggest the top boards and maybe the legs) but this step is not needed. I have found it better to stain these first and then glue them into place.

The box is now complete. Well after adding your plastic planter box with some flowers!

COST:

I love knowing how much things will cost me. So here is a cost break down minus tools and stain!

2×4’s = $24 ($8 each)
2.5 inch screws = $9.50 (about 85 screws)
plastic planter = $8

TOTAL COST = $41.50

So for less than $50 you can build a custom wooden planter box. What do you think? Any questions?

BONUS: I have created a video of the process!

DON’T WANT TO DIY IT?