Garden Planter DIY: You won’t believe how easy this one is!

An achievable woodwork DIY project to create a bespoke DIY garden planter

This garden planter DIY was a really fun project that I DIYed as part of my budget garden makeover. If you’re looking to enhance your outdoor space with a touch of greenery, building a DIY garden planter is a great way to start. Whether you’re a seasoned woodworker or just getting into outdoor projects, this step-by-step tutorial will guide you through creating a simple wooden planter box. One of my aims was to spend as little money as possible on this garden planter project, so I repurposed and upcycled all the materials. This resulted in a slightly ‘rustic’ look on the inside of the planter, but function and sustainability are much more important than picture-perfect aesthetics, in my opinion! This is a perfect project for small spaces like a front porch, or patio, or even larger areas like a kitchen garden. 

You will need…

Before you begin construction, gather the necessary materials and tools. If you have pressure-treated lumber, I recommend using it for this project. I sourced some roofing battens from Facebook marketplace for £1 each, which I used for the frame. I then did the cladding with leftover tongue-and-groove boards from B&Q. I used leftover garden paint, which was again a money-saver. 

Materials:

• Wood for the frame of the DIY garden planter (I used roofing battens)
• Wood for the cladding – I used tongue and groove panels but gravel boards would work.
• Brad nails or wood screws
• Compost
• Plants of your choice
• Paint or stain
  
  Optional
• Landscape fabric (to line the inside of the planter)
• Pocket hole screws & jig

Tools:

• Circular saw or handsaw 
• Drill and bits (to create pilot holes and drive screws)
• Screwdriver (or you could use a Brad nailer)
• Measuring tape (for accurate measurements)
• Safety gear (gloves, glasses & mask)

Step 1: Create a Cut List

Once you have your design in mind draw a plan – to do this, you’ll need to measure the space and decide on the size of the planter.  The next step in building your DIY planter is to create a cut list, which is basically a list of all the pieces of wood you’ll need with their dimensions. This list helps reduce wastage because you can then sort through your wood and work out the most efficient way of using it to get all the pieces you need. Top Tip: Before cutting, check what the longest lengths you need are and assign wood to them first. Once the longest pieces are accounted for, work out how to get the best use from the remaining lengths.

• Long sides: Each comprising a rectangular  
• Short sides: Cut two boards for the ends, matching the width of the long sides.
• Bottom boards: Cut enough slats to cover the bottom of the planter, ensuring there’s a little bit of space between each slat for drainage. (I didn’t use these, but I’ll come to that later).
• Side trim: I added a trim to the sides for added thickness and to hide the very top of the side slats and their screws.
• Side slats: These are the boards that will make up the sides of the planter. Cut them to the same length as the short sides.

Step 2: Assemble the basic frame

Once you’ve measured and cut your timber to the exact sizes needed for your planter, then it’s time to assemble the side frames. Use screws or brad nails for this step, and you could consider adding wood glue for extra strength, although I didn’t. To make this step as easy as possible, I bought very long (9cm) wood screws and simply screwed through the side of the longer pieces of the frame securing the screw into the top of the smaller side piece. The outcome was four rectangular frames as shown in the image above, two long for the sides and two short for the ends.

Next it was time to attached the four individual frames together to create the base structure of the planter. I did this by lining up the frames and placing a chock of wood in the corner allowing me to screw each frame into it to secure the corner. I added two long screws for each side frame, making four screws per corner. Image from above shown below…

Once the four sides are joined, you have the base frame as shown below…

At this point, I added a further batten to the top of the two sides that weren’t going to be butted up against a wall. I did this by screwing the wood into the top piece of the frame. This created a lip, under which I would attach the slats. I don’t have a good photo of this stage (sorry), so I have added one below, which jumps ahead slightly to show the slats being added, but you can see the additional piece of trim, too. While you are looking at the photo below, I’m reminded to mention that I put breeze blocks all the way around the inside of the planter, this was to provide support for the soil and plants as the planter was larger but also because I didn’t want wet soil sitting against the walls or the wooden sides of the planter. One of the walls was a house wall, so I left a gap between it and the breeze block to allow air to circulate and ensured that the planter wasn’t higher than the damp-proof course level. By reducing contact between the wet soil and the wooden planter structure, I hope to increase its lifespan.

Step 3: Attach the slats to your garden planter DIY

Next, measure and cut the side slats. I repurposed old tongue and groove panelling and cut to size. Then it was time to attach the side slats using short wood screws. Be sure to drill pilot holes first to avoid splitting the wood. Start by attaching the side slats to the long sides of the planter, making sure the slats are clicked into each other if you also use tongue and groove panels.

Step 4: Build the base of the garden planter DIY

Step 5: Attach the Landscape Fabric (optional)

Depending on what is underneath your planter base, you might opt to add landscape fabric aka weed membrane. If your planter is going onto soil, then you probably won’t want to complete this step, instead allowing the roots to penetrate the soil below. If your planter is going onto slabs or decking for example adding fabric will keep soil from escaping through the drainage holes. Simply line the inside of the planter with landscape fabric. Cut the fabric to fit, and use a staple gun to attach it to the inside edges of the planter. This layer also helps in preventing weeds from growing inside your planter.

Step 6: Paint your DIY garden planter

Now that your planter is assembled, it’s time to give it a final touch. Sand down any rough edges, and fill in any visible screw heads with wood filler if desired. If you’re using untreated wood, consider applying a sealant to protect the wood from the elements. I knew I wanted to paint the planter to protect the wood and match the other DIY planter I had made and located close by. I used garden paint from Cuprinol in the shade of natural stone, and it instantly lifted the finished planter and made it sing.

Step 7: Fill and Plant

With your planter box complete, place it in a spot that receives full sun (or partial shade, depending on your plants’ needs). Add a layer of gravel board or stones at the bottom of the planter for additional drainage. Next, fill it with peat moss and soil, and then add your plants or seeds. I added broken-up hardcore instead of gravel as I had lots left over after a recent DIY project, and this was a good way to get rid of some. I shared a reel of the build process for this garden planter DIY over on my Instagram, watch it here…

Top tips for garden planter DIY

If you’re working with limited space, consider making a raised garden bed or container garden. Raised garden beds are a great option for those with poor soil quality or limited mobility. Don’t forget to water planters that are undercover and won’t get the rain.