How To Build a Stone Planter

Once the area is roughly excavated, set up a grid of level lines so that you can check your depth. Drive stakes near each corner and every 2 feet along the sides. Beginning at the uphill end, stretch the line between two stakes about 4 inches off the ground and level it using a line level. Instead of tying the line in place, notch each stake so that you can easily unhook it while leveling the base. Work your way around the perimeter line, leveling as you go, then add level lines stretching side to side to create the grid. Measure from the level lines to the base of the excavated area. Dig or fill as necessary until the entire base is level and equidistant from the lines.