Determine the size of the bench planter needed for the area. Consider whether the planter will be placed in an outdoor or indoor location. This will affect wood choices.
Purchase hardwoods, such as redwood, for an indoor location that will not be exposed to the elements or pressure treated lumber for an outdoor bench planter. This wood can be purchased and cut to desired length at a local lumberyard or home improvement store.
Buy the required hardware. Galvanized screws work best for this project, yet nails can be substituted. Purchase quality wood glue as well.
Create a bench frame from the 2-by-4s, cut to size. Place smaller slats across the top of the frame to form the bench top. Assemble the end pieces and attach to the finished bench top.
Assemble 2 end planter boxes with the pre-cut lumber using the galvanized steel screws. Attach the two end boxes to the finished bench section also using screws.
Finish the project with quality stain and allow to dry.