A basic instruction to create a wooden growbox for bonsai
It really is very easy to build a basic growbox for your trees. Besides some bits of wood, all you need is a few screws, and tools. With this you can build a basic growbox for bonsai yourself in under ten minutes. This manual creates a growbox of 40*40 cm (inside) and 11cm tall (inside). With slight adjustments you can of course create a larger, smaller, deeper of shallower box.
Images and design courtesy of David Roussel.
So.. What do you need for a basic growbox?
32 screws of ~35 mm long
4 Bottom slats of 400 x 90 x 15 mm
3 Support slats of 400 x 40 x 25 mm
2 Short side slats of 400 x 150 x 15 mm
2 Long side slats of 430 x 150 x 15
Carpenters square (Or a piece of A4 paper)
Put the bottom together
Take the three support slats. Lay these on the ground, parallel and evenly spaced. The outer two should be exactly so far apart that a bottom slat exactly covers them from side to side. Put the 4 bottom slats on top of these support slats, so that they form a perfect square, as in illustration 1. Use the carpenters’ square or piece of paper to make the angles perfectly square. The bottom slats should now be 1cm apart. At each intersection of support and bottom slat, insert one screw.
Add the short side panels
The short side slats are now placed on their side, against the created bottom section, on opposite sides of the bottom section. The ends are flush with the ends of the bottom section. Screw these in place to the support slats.
Add the longer side slats
The long side slats are now place on the other two opposing sides of the bottom section. Screw these to both the support slat, as well as to the short side panels.
The basic growbox is now done. When you fill this with substrate, you should use a fine mesh at the bottom to avoid the substrate falling out.