Use wood stakes and string to lay out the size and shape of your flower bed. With bricks, you can easily create circular, triangular or rectangular flower beds. If you're creating a curved or round bed, use flour to outline the shape.
Measure the perimeter of your flower bed with a tape measure or a garden hose. You'll need about four bricks for every 3 feet in length of the wall and four bricks for every 1 foot of height. Consider the soil to determine the height of the brick wall. For clay or sandy soil, a higher flower bed offers more space for adding native topsoil and compost.
Clear grass and other growth from the area where you plan to build the wall. Dig a trench 6 inches deep around the perimeter of the flower bed. If the ground is not level, continue to dig until the shallowest end of the trench is a minimum of 6 inches deep.
Spread a layer of gravel over the trench. Use the flat end of a rake to smooth the gravel.
Follow the instructions on a bag of mortar to mix your first batch of brick adhesive.
Use a trowel to smooth a layer of mortar over the trench, about the length of three bricks at a time.
Press your first brick in the mortar. Apply mortar on the short ends of the brick before adding it to the wall. Lay the next two bricks end-to-end, about 1/4 inch apart. Tap the bricks with a rubber mallet so they are level. Use the trowel to remove excess mortar that presses out between the bricks.
Work your way along the foundation of the flower bed wall, laying three bricks at a time until you complete the first layer. Use a level to make sure that the perimeter of the wall is even.
Apply mortar at one corner of the wall. Add the next level of bricks over the corner, placing them opposite to how they fall in the layer below. Build a lacework from the corners in to ensure the stability of the wall by following a pattern of one stone over two.
Lay three bricks on both sides of each corner until you reach the desired height of the wall. Place the final bricks along the straights of the walls once the corners are complete. Add coping or other finishing top to the wall for a decorative finish and to prevent frost damage.
Give the bricks at least four days to dry before filling in the flower bed with soil and flowers.