An obelisk can be used in the garden as a purely decorative element or as a practical feature to support plants. This article will guide you through the process of making a timber obelisk with a 50 cm square base, 1.5 m high; however, you can adapt the measurements to make your own design.

Materials

• 2.5 x 5 cm x 1.8 m lengths (10) of pressure treated timber
• marine ply or pressure treated timber 25 cm x 25 cm - with chamfered edges
• 38 mm x 18 mm tiling battens to make the trellis

Method

1. Paint or stain the timber to match other timber in your garden, either using outdoor paint or wood stain. Alternatively, dilute an interior paint in a 1:3 mix with white spirit or water according to the type of paint.
2. Make a frame for each of the four sides using the 2.5 x 5 x 1.8 m treated timber. These should measure 25 cm at the top, 50 cm at the base, with the base located 30 cm from the bottom of the timber posts. This will provide the obelisk with four 30 cm 'feet' that can be set into the ground.
3. Mitre the corners at the top of each frame, and make notch joints at each end of the base of the frame to fit into the sides.
4. Mark out the midpoint of each frame - 12.5 cm at the top and 25 cm at the bottom.
5. Attach a piece of string to the frame between the top and bottom mid points.
6. Take a piece of tiling batten and set this with one end on the top mid point at an angle of 45°. Where it meets the side of the frame, set another piece at 90° to it, so that it runs across to the opposite side. Don't fix these into position, just lay out the pieces. Continue laying the pieces until you reach the bottom of the frame. This should provide a zig-zag effect.
7. Starting again at the top of the frame, set another piece of tiling batten at the mid-point, this time running it at 45° in the opposite direction as the first piece you laid. Continue laying pieces as before, so that a diamond pattern is produced. The battens should intersect along the string line.
8. When you are happy with the spacing, trim the tiling batten neatly, and secure the pieces firmly into place down the sides and where they intersect each other in the middle.
9. Continue until you have completed all four frames.
10. Attach the four frames to the top plate (25 cm x 25 cm marine ply or pressure treated timber) with the trellis pieces outermost. Use screws to produce neat joints.
11. Position your obelisk in its finial resting place. The 30 cm extra timber at the bottom of each side should be secured into the ground - dig small holes with a trowel to install it.