A planter is a box form of container gardening that provides people who lack any garden space an opportunity to grow plants of their own. Grow tall or cascading flowers or plants, herbs or berries. Planters from a variety of material can be made such as wood, PVC pipes, fiberglass, terra cotta or even metal. Those made from plywood sheets have the advantage of being lightweight, and thus very portable, even when filled with soil. Build your own lightweight planter to add a splash of color against the background.
Decide the size and shape of your planter. Try to make several small sized ones rather than one long one. You can keep it as deep as you want; however, a depth of 6 to 9 inches provides sufficient space for roots to spread. Also try to keep it up to 2 feet wide. You can make your planter angular, square or rectangular, but the latter two are easier to work with in the beginning.
Purchase a 1-inch thick sheet of cedar plywood from a hardware store. Cut five pieces to size with a handsaw. That will include two identical long pieces for the front and back, two identical short pieces for the edges, and a base piece as wide as the edge piece but equal in length to the two long pieces. Make sure you measure and mark the measurements on the plywood and cut very carefully over the lines.
Drill ½ to ¾-inch drainage holes in the base, spaced 6 inches apart. Place it on a flat and even surface.
Hold the front flush against the base piece, ensuring their tops are aligned and at the same level, and butt them together with decking screws after every 4 to 6 inches. Check the joint to make sure it is firm and secure.
Hold one of the short pieces in place against the back piece and secure it in place with deck screws that penetrate through the base and front piece. Repeat the procedure to join the other short side to the structure.
Lower the back piece in place, aligning it so its top is even with the tops of the other sides. Attach it to the structure with woodscrews. Your rectangular lightweight planter is now a box without a lid or base.
Turn it around so its base-side comes upwards, and lower the base piece into the cavity, ensuring it rests securely on the edges, before butting it into place.
Sand the planter to remove blunt edges and give it an overall smooth look. It will also help paint adhere to it better. Select a clear or colored paint, and apply a coat or two to make your planter stand out and protect it from natural elements.