Steps for Building an Accessible Garden Bed:
1. Mark the outline of the garden bed onto the grass with line-marking spray paint.
2. Remove the grass from the area with a grub hoe. Shovel the grass into a wheelbarrow and re-plant elsewhere.
3. Dig a 6-inch-deep x 6-inch-wide trench around the perimeter of the garden bed.
4. Set the first 6x6 timber into the trench, check it for level, then pack dirt around it.
5. Drill a ½-inch-diameter hole through the timber, then use a rotary hammer to drive a ½-inch-diameter x 48-inch-long reinforcing bar through hole and into the soil.
6. Disconnect rotary hammer and use a sledgehammer to pound the rebar flush with the timber. Repeat, inserting one rebar pin every 4 feet.
7. Use a 16-inch beam saw to cut timbers to length. Treat all end cuts with wax sealer.
8. Complete the bottom course of timbers, then install the next course, making sure to overlap the end joints in the course below.
9. Secure the timbers by using an impact driver to drive in 8-inch-long timber screws; space the screws 4 feet apart.
10. Continue building the wall until it's five courses high.
11. Cut and install two 6x6 cross braces to the fifth course. Fasten the braces with timber screws.
12. Cut and install the sixth and final course of 6x6 timbers.
13. Drill ½-inch-diameter weep holes through the second course of timbers; space the holes 4 feet apart.
14. From inside the raised bed, cover each weep hole with a pile of gravel.
15. Fill the raised bed with planting soil.