Rather draw it in 3D first?
Raised bed in 3D
A raised bed for vegetables, from scaffold boards, in three lessons.
FreeThen make it for real · a morning · Beginner
Make a raised bed
Three scaffold boards, six posts and a capping to sit on, then soil and something to grow. Print this page and take it to the garden.
- 1,800 long, 900 wide and 478 high
- Three scaffold boards, one length for the posts and two of decking
- About 639 litres of soil to fill it
Rather draw it in 3D first? Raised bed in 3D: three lessons
What you need
To buy
- Scaffold boards, 225 × 38 mm: 3 boards, 3.9 m long
- Treated timber for the posts, 50 × 50 mm: 1 length, 3 m long
- Decking boards for the capping, 120 × 28 mm: 2 lengths, 3 m long
- 50 exterior screws, 5 × 70 mm, and 30 decking screws, 4.5 × 50 mm
- Heavy polythene or pond liner to line the inside: a strip 5.1 m long and at least 450 mm wide
- About 639 litres of topsoil and compost, half and half
- Exterior wood treatment, if the scaffold boards aren't treated
Tools
- A tape measure, a pencil and a square
- A spirit level and a spade
- A hand saw or a circular saw
- A drill with a 3 mm bit and a countersink, and a screwdriver bit
- Two clamps, and a staple gun for the liner
Scaffold boards are heavy: lift them with a bend in your knees, or two of you. Wear gloves for treated timber, clamp each piece down before you cut it, and keep both hands behind the blade.
Cut list
18 pieces
Scaffold boards 225 × 38 mm, posts 50 × 50 mm, capping from decking boards 120 × 28 mm. Sizes in millimetres.
| Piece | Size | How many | Note |
|---|---|---|---|
| Long board | 1,724 × 225 × 38Between the ends, two rows at the front and two at the back | 4 | Between the ends, two rows at the front and two at the back |
| End board | 900 × 225 × 38The full width, two rows at each end | 4 | The full width, two rows at each end |
| Post | 450 × 50 × 50One in each corner, one in the middle of each long side | 6 | One in each corner, one in the middle of each long side |
| Capping, long | 1,800 × 120 × 28Along the front and the back, flush with the outside | 2 | Along the front and the back, flush with the outside |
| Capping, end | 660 × 120 × 28Across each end, between the long ones | 2 | Across each end, between the long ones |
A different size? Keep the ends the full width and the long boards 38 shorter at each end than the bed. Over about 1,200 long, put a post in the middle of each long side so the boards don't bow under the soil.
5 steps
Step 1 of 5
Mark out the ground
- Pick a spot that gets the sun most of the day, as level as you can find.
- Mark out 1,800 × 900 with pegs and string. Measure the diagonals: 2,012 each when it's square.
- Lift the turf inside the string, or cover the grass with cardboard: it rots down under the soil.
Step 2 of 5
Make the two ends
- Lay two end boards flat on the ground, edge to edge: an end 900 long and 450 high.
- Put a post at each end of them, 38 in from the end (an offcut of scaffold board is the spacer) and level with the top.
- Drill 3 mm pilot holes and screw through the boards into each post, two screws a board. Make the second end the same.
Step 3 of 5
Join them with the long boards
- Stand the two ends up on the marks, posts inside, and lay a long board between them at the bottom, front and back.
- Screw through each long board into the corner posts, two screws at each end, then the top row the same way.
- Put a post in the middle of each long side, level with the top, and screw the boards to it. Check the diagonals again: 2,012.
Step 4 of 5
Screw on the capping
- Lay a long capping along the front, flush with the outside at the front and both ends.
- Drill and screw it down into the top of the boards about every 300, 19 mm in from the outside so the screws go into the middle of the board.
- Do the back the same, then the two end cappings between them.
Step 5 of 5
Line it and fill it
- Staple the liner round the inside of the boards, from the top down to the ground, so the soil doesn't sit against the wood. Leave the bottom open so the water drains.
- Fill it with topsoil and compost, about 639 litres, and firm it down as you go.
- Water it and leave it a few days to settle, then top it up before you plant.
Raised bed in 3D: three lessons