Start by cutting the pickets into the necessary pieces for your planter. This includes eight legs, four top and bottom boards, and wall boards and trim pieces. Be sure to use bevel and miter cuts for a tight fit.
Use a pocket hole joiner to create holes for your screws, and set the depth collar for one-half inch. Use exterior deck screws to secure the pieces together.
After the frame is assembled, you can start building the walls. Measure and mark the wall boards to be placed on the side frames. Pre-drill holes and use one-inch screws to fasten the walls to the frame.