Preparing the ground
The usual way to prepare the ground for planting was to double dig. We not longer do that as it has been shown to damage soil and reduce its fertility. After the square metre bed trials of 2010 digging was proven to be totally unnecessary.
Edging the bed
When you have finished digging you can edge the bed with timber or other suitable material. Avoid using pressure treated timber as the preservative used may contain chemicals which could leach into the soil. The board should be 4”- 6” deep but you can use a higher surround if required. Some people have used upturned bricks, roofing tiles and concrete blocks. It does not have to be timber!