What’s nice about a deep raised bed is that there is no need to remove the sod underneath it. You can simply fill it with soil and start planting.
DEEP RAISED BED. A deep bed, such as this one, holds enough soil to keep plantings moist for longer stretches of time than a shallow bed would.
Lumber
4"×6" Douglas fir (ten 8' lengths)
Supplies
Fifty-six 6" timber-lock screws
Tools
Tape measure
Pencil
Carpenter’s square
Wood saw
Heavy power drill
½" spade drill bit
⅛" extra-long twist drill bit
Driver bit that comes with the screws
Cutting the lumber. Cut the 4"×6" into ten 65¾" lengths for the long sides 
and ten 29¾" lengths for the short sides 
.
Constructing the bed. Assemble the first layer on the ground by using two longer lengths and two shorter lengths to form a rectangle, as shown in fig. 1. Lay a second layer atop the first, alternating the timbers in the corners so that the joints are staggered (fig. 2). To prevent the wood from splitting, predrill holes, ½" deep and ½" wide, for the screws in the top layer, following the pattern provided in fig. 2. Then fasten down the wood, countersinking the screws so they are flush with the surface. Continue in this way, adding three more layers to the planter for a total of five layers.
BUILDER’S TIPS
Turn the boards so the best face is showing. When fastening each layer, flush up the edges and tack the four corners together before sinking the other screws.
FIG. 1
FIG. 2
