A planter box allows a home owner to grow herbs, flowers or plants anywhere inside or outside the house. This form of container gardening adds color to a porch, outside a window, on a step, in the garden, indoors, or any particular spot that needs a little sprucing up. Planter boxes are made using a variety of materials such as ceramic, plastic, wood, metal or terra cotta, but wood is widely preferred because it has a natural appearance. Make a planter box yourself to cut down on costs and customize it according to your needs.
Determine the spot where you want to place the planter box so you can measure the appropriate height, length and depth of the planter box accordingly. Ideally, it should be 10 to 12 inches deep and not more than 3 to 4 feet wide.
Also decide the shape of the planter. An easy shape for starters is a simple square or rectangular planter box.
Purchase good quality, rot resistant wooden boards from your local hardware store, or cut them to size with a saw. You will need five boards for your planter box- two identical boards for the short sides, two identical long boards for the front and the back, and a board for the base that is as wide as the short side but equal in length to the front and back.
Take the base board and drill ½- to 1-inch drainage holes on it, spaced evenly apart.
Hold the front board and place one of the short sides flush against it. Make sure the joint is even and flush, and drill a galvanized wood screw through the front board, an inch below the top edge, which will penetrate through the side and join the structure together. Drill another wood screw an inch above the bottom edge. Check the structure to make sure it is secure, or reinforce it by drilling another screw in the center, if necessary.
Hold this L-shaped structure and place the back piece flush against the short side, making sure the tops are at the same level. Drill wood screws to connect it to the structure. Once secure, fit the second short board in its cavity between the front and back boards, and secure it in place by drilling wood screws at the top and bottom edge. Your planter will resemble a box with no lid or base.
Turn the planter over so its base side faces upwards, and lower the base piece over it. Secure it in place by drilling wood screws to connect it to the front, back and sides of the box.
Sand the planter with medium grit sandpaper to remove any sharp edges, and apply a coat of exterior paint so it can withstand natural elements.