Build a DIY Simple Planter Box

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The best gardening advice I’ve received in my freshman year of growing is “You will harvest many lessons from your first garden.” Man, oh, Man. This is the truth.. and possibly the name of my future memoir. We dove in, head first, to the world of backyard gardening this Summer with little to no knowledge and have already made adjustments for next year including this DIY Simple Planter Box.

One of those lessons was how quickly Strawberries spread. I had no idea! When we bought our cute little strawberry plant, I potted him in a nice big patio pot and within a few weeks, my little guy was picking off a berry or two a day to snack on. It was so much fun for him to water and harvest and quickly became our favorite potted plant on the garden patio. I wasn’t aware, however, that the cute little vines hanging over the edge were trying to root in my yard.. whoops! This strawberry plant was climbing out of the pot and ready to take on the yard. He was in need of a bigger home.

A quick internet search informed me that Strawberries need to be planted in soil that is 8-10 inches deep and that they will spread out as much as they are able. I decided to build a planter box that would give the plant about 3 ft to spread while keeping it low to the ground and toddler’s arm length across so my kiddo could still be the caretaker of the “Berries.”

The dimensions of this DIY Simple Planter Box (including the legs) ended up being 20.5″ x 36″ x 15.5″.

I built my planter with scrap lumber we had in the shop, but, if I were to purchase lumber for this project, I would use the following Cut List:

• Six 1″x4″x36″ (long side panel “walls”)
• Six 1″x4″14″ (short side panel “walls”)
• Four 1″x4″x34.5″ (bottom of box)
• Four 4″x4″10″ (planter legs)
• Three 1″x4″x14″ (ribs for bottom of box)
• Three 12″ Furring Strips (mine were 3″ wide)

I would also have prefered to purchase Cedar boards to use for outdoor projects like this one, but, ended up using the Pine we had in the barn. While cedar is ideal, it is a bit pricier. If you’d like to use pine, make sure you use a good water resistant Deck Stain to help protect your finished DIY Simple Planter Box.

To build the side “Walls” of your planter – you have a few options. You can secure the boards to one another using Pocket Holes (made with a Pocket Hole Jig – I use this one!), Furring strips, or two screw mending plates.

If you don’t have a pocket screw jig, the furring strips or mending plates would both work well and be a simple way to create the four “Walls” for your planter. No matter what version you use to attach your boards from behind, make sure you are using exterior screws in an appropriate length so they don’t pop through the front.

The bottom panel of my box was built with scraps from the shop, and was only three boards wide, but, your bottom will require attaching 4 boards to one another. To secure these boards, you’re going to use the Furring strips instead of pocket screws or plates. These strips will offer a little more stability to hold the weight of the soil in your planter.

Once you have the four walls and bottom built, you’ll attach your walls together. The BIG thing to remember here is the Smaller Side panels are going to fit IN BETWEEN the Longer front and back panels.

To secure the panels at right angles, I used some of my FAVORITE miter clamps to hold the panels up while I piloted holes and drilled the “walls” into one another. These clamps worked like a dream to hold the box steady while I was drilling.

Once all four walls were secured together, I stood it up on end and shimmied the bottom piece into place.

To create support ribs for the bottom piece to sit on, I placed the remaining boards into the bottom and screwed them in from the front and back of the box.

To secure the legs, we simply drilled and screwed down through the bottom of the box, through the rib and into the 4×4 posts. The easiest way to do this was to set the box upright, square up the legs in all 4 corners and then put 2″ outdoor screws down through all the pieces.

The only things left to do at this point are to sand (if you’d like), stain (to waterproof the exterior) and PLANT! Our strawberries are so much happier now that they have room to spread out and I can’t wait to see what kind of a haul we get from them next Spring!