How to Build Curved Low Concrete Block Walls

Lay a string along the proposed path for the wall. Use spray paint along the string to show where to dig out the soil.

Dig a straight-sided trench along the path that is two blocks deep and 1-1/2 blocks wide. Level the floor of the trench with a hand tamper and cover the bottom and sides with landscaping fabric. Fill the trench to a 1/2-block depth with coarse gravel.

Place the first edge block at the end of the trench, with the face side pressed against the trench wall covered by the previously installed landscaping fabric. The backside of the block should be toward any slope or soil that will butt up against the wall. Lay the next block against the first one and hit the side of the second block several times with the maul to ensure it rests snugly against the first block. Lay down two more blocks then place a carpenter's level across the top to ensure the blocks are level. Continue to lay the blocks, checking for level every four blocks, until the foundation is finished. If necessary, adjust the gravel underneath the blocks if they're uneven.

Start with a half block edge to set the next row in place on the foundation. Set the tongue in the groove, according to how your particular block is designed. Hit the top and side two or three times with the maul to ensure a good seating. Continue to lay the second row with full-sized blocks and use the maul to seat them solidly on top of and next to the other blocks. You will need another half block at the end.

Begin the third row with a full-sized edge block and construct it as you did the second row. The fourth row starts and finishes again with a half-sized block. Some manufacturers have special top row blocks you can finish the wall with.

Tug the landscaping fabric so that it is up against the back trench wall. Fill in the gap between the foundation blocks and the back wall of the trench with more gravel until you reach the top of the soil. If the wall is a retaining wall with soil against the back end, then also place landscaping fabric over the top of the gravel before you add soil on top of it.