You can use pressure-treated or cedar wood for this project. If you choose pressure-treated, make sure to allow the wood to dry for a couple of weeks prior to staining. To reduce the risk of splitting the wood, drill pilot holes for all instances using the 1-5/8" deck screws. Make sure not to drill through to the opposite side. This build is pretty straightforward. Be sure to offset the placement of pocket holes on the side panel assemblies. Since you use them on all four panel assemblies, the screws will hit each other when going into the 2 x 2 legs if you do not. The inner shelf can be placed at any position inside the planter to accommodate your desired plantings. Overall dimension: 24" x 17" x 17" Set up each group with a pocket hole rib on the outside. You will use the pocket holes in Step 3. Attach a rail to the top and the bottom of each rib grouping with wood glue and 1-5/8" outdoor deck screws, using two screws at each contact point. For a cleaner look, drive the screws from the rib side (what will be the inside of the planter). When driving the screws, be careful not to drive the screws too far and have them poke out the other side. For the first short X, set another length of 1" x 2" board in place from an adjacent corner to where it meets the first X piece. Mark the angles at either end and cut so that the board fits snug. Repeat for the second short X. Attach both using wood glue and 1-5/8" outdoor deck screws, screwing from the inside. Cut your shelf planks to length. Attach them to the shelf cleats using wood glue and 1-5/8" outdoor deck screws.
