Many planter box plans and instructions are too complicated for a beginner to complete. Even if you've created items from wood before, a simpler project can be rewarding when it's finished quickly. If there is a choice of wood, cedar and redwood are the best for outdoor use, because they are rot-resistant. You may build a planter box from any type of wood, but it will last longer if you seal it.
Mark and cut two pieces 1-by-10 lumber, 2 feet long. These boards will be the front and back of the planter box. Mark and cut two pieces of lumber, 10 inches long. These are the sides or ends to the planter box.
Place your cut boards so they make a frame shape. The shorter, side-end boards should fit crosswise inside the ends of the two longer boards.
Spread wood glue over the cut ends of the shorter boards. Stick them to the longer boards at the ends, keeping the frame shape. Let the glue dry overnight.
Attach four screws, evenly spaced, across the front and back boards and into the sides of the shorter boards, where they are glued together. Use your drill and attachment for screws. This will make a sturdy frame to your planter box.
Measure the final dimensions of your wood frame. They should be approximately 2 feet long and 11½ inches wide. Although the lumber is called 1-by-10 inches, it is actually only ¾ inch wide.
Mark the final measurements of the wood frame onto a piece of plywood. Use an electric saw to cut along the markings.
Put glue on the top edges of the wood frame. Place the cut piece of plywood on top of the glued wood and press gently. Allow it to dry overnight.
Screw the plywood bottom to the wood frame with rust resistant screws. Attach a screw about every 5 inches over the glued area.
Use a round bit and the drill to create random holes through the plywood, for water drainage.
Put the planter box right-side-up. Sand any rough spots. Paint, stain or seal your planter box, with an exterior product, if you desire.