Today I’m going to teach you how to build a DIY planter box that is great for flowers & herbs. It’s cheap to make, easy to move around, and the perfect addition to spruce up your outdoor area.

The dimensions of this DIY planter box are 37.5”x12”x10.5” I made the square balusters 12” which added an extra 1.5” so they would help hold my planter box up off the ground. I don’t plan on moving mine & the area I’m placing it is pretty sandy and I didn’t want the whole planter box sinking down. If you don’t want them sticking out the bottom like mine, measure the balusters at 10.5” long.

What Kind Of Wood Should I Use For A Planter Box?
Cedar is going to be the best choice if you are going to be putting herbs in them as well for eating and cooking with. You don’t want to use pressure treated wood because the chemicals will leach into the soil and go into the herbs. Cedar is also a beautiful wood that doesn’t need any staining since it has a nice color to it. It looks more organic compared to pine lumber. Cedar is naturally pest and rot resistant.
What Soil Do I Put In A Planter Box?
We have some soil/compost mixture left over from a delivery we got from a local landscape company. You can use any potting soil you would like but you can also use garden soil and compost if you would like as well. I like to make sure there is some sort of natural fertilizer/nutrients for the flowers & herbs.
This post contains affiliate links, which means I make a small commission at no extra cost to you. See my full disclosure here.
Materials You Will Need
- Miter saw
- Tape measure
- Pencil
- Hammer
- 3 1”x4”x8ft Cedar boards
- 2 Cedar 2”x2”x48” square balusters
- 2” Galvanized Spiral Nails

Steps For How To Build A DIY Planter Box
Step 1
On each of your cedar board measure out 3ft, and make the cut. Repeat once more on each of the boards. You will have six 3 ft long boards for the front and back of the planter. The leftover boards you will cutting directly in half and those will be the sides of your planter box.
Step 2
Measure out 10.5 inches on one of your square balusters. Repeat this process until you have 4.
If you want the balusters to be sticking out the bottom an extra 1.5, measure them at 12” instead.
Step 3
Lay down two of your balusters and place 3 of your 3 ft long board on top. Make sure the balusters are lined up evenly at the ends. Hammer in two nails at each end of each board. Repeat this process for the other side of your planter.


Step 4
Stand the front and back of your planters up long ways and hammer in the 10.5” sideboards into the balusters. I found this to be the easiest way if you are doing this project solo. The ground also gives the board something to brace against as you are hammering in the nails.
You will want to make sure your nails aren’t lining up with the nails from the front and back pieces of the planter or they won’t go in all the way.

Do Planter Boxes Need To Be Lined?
If you are building a planter box that will be up off the ground you don’t need to line it with anything to prevent weeds. Planter boxes you are putting directly on the ground so the soil is in contact with the grass or dirt, you can put a layer of landscape fabric to help with weeds but it’s not necessary. If any weeds pop up in your planter box it is a very small place to maintain.

Pin It For Later

Thank you for reading & if you try this DIY, tag me on Instagram! @our1sthomestead
You Can Find More Blog Posts Here
How To Make A DIY Cucumber Trellis
How To Make DIY Shaving & Body Oil
15 Mother’s Day Gifts For The Minimalist Mom
Alfredo Sauce From Scratch Ingredients
Until next time,
Ellen
Leave a Reply