How to Make a Retaining Wall Out of Bricks in Landscaping

Mark the line of the wall with stakes and mason's twine; make sure it is straight. Dig a trench with a shovel a foot deep and as wide as half the height of the wall -- 18 inches for a three-foot wall, for instance. Align the back side of the trench with the bottom of the slope to be retained. Lay two inches of gravel in the bottom of the trench and compact it with a hand tamper. Make the sides of the trench vertical.

Pour concrete into the trench. Spread it with a board and press it firmly into all areas of the trench. Use a flat mason's trowel to smooth the top and a four-foot level on a board to get the top level the length and width of the trench, with the top just below the level of the ground. Let that concrete footing cure for a week.

Snap chalk lines to mark the outside edges of the two sides of the wall on the footing. Dry fit some bricks to test your pattern. Lay bricks on the footing in the style you choose. Use a running bond, where each brick overlaps those underneath by half a length, for the simplest pattern, Lay a row of bricks lengthwise on each side of the footing. Start a second row with a brick laid across the two end bricks; this adds support and also starts the half-brick bond pattern.

Remove the dry fit bricks and mix mortar in a wheelbarrow or large container. Mix only enough for about half an hour of work; stop work and discard mortar if it starts to dry out and gets crumbly. Lay the first bricks with a half-inch of mortar spread with a pointed mason's trowel on the bottom and end. Set the bricks in place and check them a with a level.

Lay a base course on both sides, adding mortar on the gap in the center; the two rows should be as wide as the length of one brick. Start the second course with a brick crosswise at the end. Lay running bond bricks for that course, but put a crosswise brick every four bricks, to tie the two sides of the wall together. Check constantly with a level to make sure the bricks are level.

Build the wall to the desired height and finish it with a cap of bricks laid crosswise. Lay four to six inches of gravel at the base of the finished wall, once it has set firmly, for drainage. Backfill behind the wall with dirt, stopping slightly below the top of the wall. Form a swale or depression in the ground at the top, just behind the wall to aid in drainage.