The first step is to construct the top and the bottom frames of the box with 1 x 2 cedar strips. Now, join two cedar strips that are 26 inches in length with two other cedar strips that are 13 inches long to form a rectangular frame. Make sure that you measure the wood correctly before cutting it.
All the cedar strips should be accurately cut to the precise measurement. Apply a bit of the strong glue at the edge of the wooden board, and then nail the boards together with a single galvanized nail. To hold the box structure more securely, drill along the corners with the handheld drill. Insert the screws in all the drilled holes and twist them firmly.
Now, place the two frames on their sides and apply some glue to the inside of the bottom frame. Attach the four side panels on each side and nail them from the inside to securely hold them.
Ensure that the panels fit properly on the frame. Apply a little glue on the inside of the bottom frame and attach the bottom panel. Make sure that the bottom panel fits perfectly over the planter box, and adjust until it fits snugly. Cut four wooden pieces which are around 2 inches in thickness and width and 13 inches in length.
Attach these four pieces at the bottom of the box to form the base. Sand the edges of the box with a sandpaper to smooth out the edges and corners. Drill a few holes in the bottom panel for drainage. You may apply a wood stain or paint. For a rustic look, you can even leave it unvarnished and unpainted.
Place a pond basket about 5 inches in diameter on top of the plastic, and trace around its circumference. With a sharp knife, cut out the traced circle. Now, set the pond basket right-side up on the cut plastic tub, and mark the height of the basket on the side of the tub.
Cut the top half of the tub using the mark as the guide. On the uncut tub, drill a 1 inch hole. Slide the tub with the large bottom hole with one with the 1 inch hole. Place the pond basket inside the tubs, and fill it with potting soil. Through the 1 inch hole in the tub, slide a 3 foot length, 1 inch diameter PVC pipe for drainage.