There are many cool home gardens – indoor and outdoor, but this is not only a garden but also a pond. First cut your plywood of the measures you need into boards and apply polyurethane glue to a long edge of the floorboard. Glue and fasten the boards using screws. To create a quarter section for a planting bed, glue the remaining 15-inch length in place as a divider. Secure with nails driven through the sides and floorboard. Position and nail the cleats onto box corners. Paint the inside of the box with rubberized sealant, or install a pond liner; on the garden side, drill two or three holes in the base to provide drainage for plants. Add water and pond plants to the other compartment, as well as a fountain pump.