DIY Raised Planter from Reclaimed Decking
Step-by-step guide made from DIY With Emma's YouTube video.
Learn how to build a sturdy, raised garden planter by upcycling old decking boards. This project is a cost-effective way to create custom-sized planters for your outdoor space while recycling materials you may already have.
- Difficulty: intermediate
- Time: about 1 hours
Safety
- When using a circular saw, ensure the wood is securely clamped or stabilized before cutting. The creator's method of using her foot is not best practice.
- Rags soaked in boiled linseed oil can self-combust as they dry. Always lay them flat on a non-flammable surface like concrete or metal away from your workshop until they are fully dry and stiff before disposal.
Must know before you build
- Treat all raw cut ends with boiled linseed oil; lay BLO-soaked rags flat to prevent self-combustion.
- Secure wood with clamps for circular saw cuts; never use your foot for stability.
- Use a combi drill for better torque control when driving screws into reclaimed wood.
- Line planter with reclaimed soil bags; use waterproof decking tape to seal seams for durability.
- Employ Hugelkultur layers (twigs, cardboard) to reduce soil cost and improve drainage.
Tools
- Tape measure
- Pencil
- Set square (Johnson)
- Circular saw (Cordless, DeWalt, DCS391, 20V MAX)
- Impact driver (Cordless, DeWalt, DCF887, 18V)
- Clamps (Quick-grip bar clamps, Irwin) (optional)
- Staple gun (Manual)
- Scissors
- Shovel (optional)
Materials
- Decking boards (Reclaimed)
- Treated wood (4, Kiln-dried, Treated, 45mm x 70mm)
- Boiled Linseed Oil (Bartoline)
- Decking screws (Torx/Star-head)
- Plastic sheeting (Reclaimed soil bags)
- Waterproof decking tape
- Sticks and twigs
- Cardboard (Recycled)
- Soil and Compost (Multi Purpose Compost, Moorland)
Step by step
Step 1: Prepare and Cut the Legs
Measure and cut four pieces of treated wood to a uniform length. These will serve as the legs for the raised planter.
- Determine Leg Height. Decide on the desired height for your planter. The creator uses leftover 45x70mm treated wood from a pergola build.
- Tip: Using wood already treated for outdoor use will help your planter last longer.
- Measure and Mark the Legs. Measure your shortest piece of wood for the legs and use it as a template to mark the other three pieces to the same length. Use a set square to ensure your marks are perfectly straight for a 90-degree cut.
- Cut the Legs. Using a circular saw, cut all four legs to the marked length.
- Watch out: The creator uses her foot to hold the wood, but it's safer to clamp the wood to a stable surface like a workbench before cutting.
Step 2: Cut the Decking Boards
Cut the reclaimed decking boards to the desired lengths for the short and long sides of the planter.
- Cut Boards to Length. Cut all the decking boards needed for the sides of the planter to your desired length. The creator bases her measurements on a previous planter she built.
- Tip: To maximize your material, measure the total length of the wood you have and divide it by three. This will give you the length for your boards with minimal waste.
Step 3: Assemble the End Panels
Assemble the two shorter end panels by screwing three decking boards onto two legs each, ensuring the assembly is square.
- Lay Out and Align the First End Panel. Lay two legs on the ground and place three of the shorter decking boards on top. Use a set square to ensure the boards are at a 90-degree angle to the legs and leave small, even gaps between the boards for wood expansion.
- Tip: Leave a small gap between each decking board to allow for wood expansion and contraction.
- Drill Pilot Holes. Drill pilot holes where you will place the screws. This prevents the wood from splitting, especially when working with older, drier wood.
- Tip: Using Torx or star-head screws provides better grip and makes driving them in easier.
- Secure the Boards. Drive decking screws through the pilot holes to attach the boards to the legs. Use two screws per board on each leg.
- Tip: A combi drill with an adjustable torque setting can give you more control than an impact driver and prevent sinking the screws too deep.
- Build the Second End Panel. Repeat the process to build the second, identical end panel.
Step 4: Assemble the Main Body
Connect the two completed end panels by attaching the longer decking boards to form the sides of the planter.
- Position the Side Boards. Stand the two end panels up and rest the long side boards on top. Overlap the side boards so they cover the ends of the short boards, creating a clean corner.
- Check for Square and Secure. Use one screw in the top board as a pivot point. Use your set square to adjust the frame until it's at a 90-degree angle, then secure the rest of the screws. Drill pilot holes first to prevent splitting.
- Common mistake: If you find your boards are slightly different widths, don't worry. Just do your best to align them and embrace the rustic look of the reclaimed material.
- Attach Remaining Side Boards. Continue attaching the rest of the long side boards to both sides of the planter, maintaining even spacing.
Step 5: Install the Base
Install two support beams inside the planter, then lay several shorter pieces of decking across them to form the base, leaving gaps for drainage.
- Install Base Supports. Measure the internal width of the planter and cut two pieces of wood to fit. Clamp these supports inside the planter at the desired height for the base and screw them in from the outside.
- Add Base Slats. Cut several shorter pieces of decking to fit across the width of the base. Lay them on top of the support beams, leaving gaps between each slat to allow for water drainage.
- Tip: You don't need to screw the base slats down; their job is just to support the liner and soil.
Step 6: Line the Planter
Line the inside of the planter with plastic sheeting from old soil bags, stapling it in place and cutting drainage holes in the bottom.
- Place and Secure the Liner. Use old compost or soil bags as a liner. Cut them open and lay them inside the planter, covering the bottom and sides. Use a staple gun to secure the top edge of the liner to the inside of the planter.
- Tape Seams and Cut Drainage Holes. If using multiple bags, use waterproof tape to seal the seams. Finally, use scissors or a knife to cut several small holes in the bottom of the liner for drainage, aligning them with the gaps in the wooden base.
Step 7: Fill the Planter
Fill the planter using a layered method (Hugelkultur) to improve drainage, save on soil, and add nutrients over time. Start with sticks and twigs, followed by cardboard, and finally top with soil and compost.
- Add a Layer of Twigs and Sticks. Place a layer of sticks, twigs, and small branches in the bottom of the planter. This creates air pockets for drainage and will break down over time to provide nutrients.
- Add a Layer of Cardboard. Place a layer of cardboard over the sticks. This will help retain moisture and will also break down over time.
- Add Soil and Compost. Fill the remainder of the planter with a mixture of soil and compost, ready for planting.
- Tip: As the bottom layers decompose over the seasons, the soil level will drop. You can simply top it up with more compost each year.