How to build a cedar planter from rough cut lumber

Do you want to build a planter to increase your curb appeal? I’m going to show you how to build a cedar planter using rough cut lumber. If you are looking to make your own planters, you can easily adapt this design to make any shape or size of planter!

This post contains affiliate links, which means I may receive a commission if you purchase anything through these links

Tools and Supplies

My husband Tony works for a Hydro company, and one of the perks is that he occasionally gets to take home used hydro poles. And did you know that hydro poles are made of red cedar? Tony also knows someone who has a saw mill and we got a stack of poles milled into rough cut cedar planks. I thought it would be perfect to use these cedar planks to make two large outdoor cedar planters.

If you aren’t lucky enough to have hydro poles lying around, you can buy cedar from a lumber store. You can build this planter with any type of wood, but the nice part about cedar is that you don’t have to finish it. It’s naturally weather resistant, and has such a wonderful smell.

These are the supplies you will need to make two planters the same dimension as mine (18″ by 18″ by 26″ tall). If you want a different size planter, you’ll have to adjust your material list accordingly. I’ve provided links to some great tool options, but there are many different options depending on your budget.

3 pieces of 12 foot long cedar plank (7″ to 9″ wide)
~14 feet of 3.5″ wide cedar board (for the top)
~18 feet of 2″ x 2″ cedar (corner posts)
Miter saw
Table saw
Palm sander
100 grit sandpaper
Pocket hole jig
Cordless drill
Deck screws
Outdoor wood glue

Step 1: Prepare Cedar Boards

I used three cedar planks that were approximately 12 feet long, and varied in width from 7″ to 9″. For the corner pieces Tony cut some of the cedar into 2″ x 2″ pieces using a table saw. Tony also cut a couple planks 3.5″ wide for the top pieces.

Step 2: Cut Planter Pieces

I cut each cedar plank for the sides into eight pieces using a miter saw, and used one piece from each plank for each side of the planters. I cut all the side pieces 14″ long. The corner pieces are 2″ by 2″, and I cut them 25″ long.

Between the three 14″ long pieces for the sides, and the 2″ wide corner pieces, each side has a dimension of 18″ wide and 25″ tall.

Step 3: Sand All Pieces

Next I lightly sanded all the cut pieces using a palm sander with 100 grit paper. This removed any big splinters and made the pieces not quite so rough, but still left them looking rustic. I also rounded all the edges to give it a more professional finish.

Step 4: Assemble the Planter Sides

First I attached the three panels for each side to the corner posts. I used my pocket hole jig to attach each side panel to the 2″ x 2″ corner posts. Then I drilled two pocket holes for each board on each side. I think you’re supposed to use a clamp when you use this jig, but I got lazy and started holding it after clamping once or twice. There were a total of 64 pocket holes, per planter, so clamping and un-clamping would have taken too much time. I tend to take shortcuts like that, but do whatever works for you.

After drilling all the pocket holes with my cordless drill I used 1.5″ galvanized deck screws to put the planter together.

Step 5: Finish The Top

To finish the top of the planter I mitered 3.5″ wide cedar boards so they would form a square with an outside dimension of 19″. This extra inch allowed for a small overhang around the edges. I again made pocket holes on the bottom side of each corner. I used two screws for each corner, after first applying a bead of outdoor wood glue.

Once I had the top square together I attached it to the planter using my pocket hole jig. With the cordless drill I screwed up from the planter into the square top with a total of eight screws.

Step 6: Add a false bottom and add soil and flowers

Last year I just put a plastic flower pot inside, and my plants did not do very well. They dried out too quickly because they weren’t getting enough water (I tend to forget to water them). This year I added a false bottom about 10 inches from the top of the planter, then filled it right up to the top with soil. Then I planted my flowers. They are doing so well this year! I pulled the planters slightly away from the wall so they are catching more rain water, and water them occasionally if they get too dry.

And that’s how to build a cedar planter!

This first picture is from this year, and the rest are from last year. The planters have weathered over the winter, but I still think they look great.

how to built a cedar planter with rouch cut lumber

The nice part about this cedar planter is you can make it any dimension you want depending on where you want to use them. I wanted two substantial looking planters for in front of our garage, so these dimensions worked great for me. Here are some other ideas for increasing the curb appeal of your home.