If you live in an apartment you probably don't have enough space to have a garden area with all the features associated with it. Most often, you only have your balcony to decorate it with flowers and plants, in a way that'll provide you with a space where for you can rest and relax. You can certainly add a small water feature in one of the corners, or at least a tabletop fountain, and accessorize with a box water garden, convenient for such small outdoor areas. Here's how you can make this water garden by yourself.
What will you need? From the materials, you'll need wood, water sealant, plastic liner, water plants like Japanese sweet flag, arrowhead, common duckweed, broadleaf, stonecrop, houseleek, deer fern, or blue-eyed grass, potting soil, pea gravel, and gazing ball or other ornament. The tools you'll need include: handsaw or circular saw, a hammer and nails, drill, wood screws, and a screwdriver.
We will first make the outer frame of the box. For this you'll need 2 pieces of 1×8 inch cedar boards that are 30 inches long for the sides, and 2 pieces that are 15 inches long for the ends of the box. After you'll assemble them with a hammer and some nails, connect them with wood screws to the bottom piece made of the same 1×8 inch wood or some ¾ inch exterior plywood, through the pre-drilled holes along the edges of the box, on every 6 inches. First start with one of the long sides, then the two short sides, and finish with the remaining long side. If you want to make a divider for a separate planting box, cut another piece of wood that is the width of your interior, and attach it with wood screws, where you feel fits the most. It is very important to fasten the end joints on all four corners as tight as possible to minimize gapping. To additionally strengthen the box, apply sealant to lengths of 1×2 inch stripes of wood and fasten them to each of the corners.
Inside the box install a plastic liner or use a water sealant (make sure it is safe for aquatic life if you plan on having fish in your water garden). For the plants you will need to provide drainage, by drilling two or three holes in the box bottom. When this is all done, fill in the box with potting soil and start creating your plants composition. Select plants that vary in size, texture and form; submerged or floating; some taller and few trailing plants. Place the floating ones on a brick, so they will sit 2 inches below the water surface. As a final touch you can paint the outside of the box, or add ornamental elements for visual interest.