How to build a DIY Timber Sleeper Planter Box

DIY Timber Sleeper Planter Box

Size: 1,800mm long × 600mm wide × 600mm highConstruction: 3 × 200mm-high sleeper courses

Materials all from Bunnings warehouse 

• 12 × 200 × 50mm × 2.4m H4 Treated Pine Sienna MicroPro Sleepers⁠
• 1–2 packs Exterior Structural Timber Screws⁠
• Approx. 7m² Heavy-Duty Planter Liner⁠
• 1 pack Galvanised Staples⁠
• Approx. 600L Garden/Planting Mix⁠
• Approx. 50L Pine Bark Mulch⁠

Tools

• Tape measure
• Spirit level
• Square
• Shovel and spade
• Rake
• Circular/drop saw
• Drill/driver
• Drill bits
• Staple gun
• Clamps
• Wheelbarrow
• Safety glasses, gloves and hearing protection

Steps

1. Mark outMark the 1,800 × 600mm area and check it is square and level.

2. Prepare groundRemove grass and loose soil. Level and compact.

3. Cut sleepersCut the 12 sleepers to size and label them.

4. Build first courseLay the sleepers, check square and level, then screw the corners together.

5. Add courses 2 and 3Stack the sleepers, stagger the joints and screw each course securely to the one below.

6. Add linerLine the inside walls and staple near the top. Keep the bottom open for drainage.

7. FillAdd approximately 600L of planting mix, leaving about 50mm at the top.

8. FinishAdd approximately 50L mulch, plant and water thoroughly.