Dimensions
- Width: no more than 4 ft (about 1.2 m) so you can reach the middle from both sides; 2½ ft if against a wall.
- Length: anything — 8 ft is common.
- Height: 6 in for greens, 10–18 in for other crops.
- Paths: leave room to work around the bed.
Materials
Wood, brick, bamboo or old tin — whatever is cheap and handy. Make sure walls don’t bow under wet soil.
Soil
A mix of good loam, compost and sand, with drainage at the base.