Directions for Building a Rock Retaining Wall

Measure the length that you want the rock wall to be in the area where you want to place the wall in the landscape. Put a stake at one end of the wall's length and a stake at the other end to mark the wall area. Measure out from each of the stakes 8 to 12 inches, depending upon the size of the rocks that you are using and put two more stake in place to mark a long rectangle on the ground.

Remove the soil in the rectangle between the stakes. Dig the trench roughly 12 inches deep.

Fill the wall trench with 6 inches of sand and line the trench with the largest rocks you want to use in the wall. If you are building a wall higher than approximately 2 feet, or one that you would like for people to be able to sit on, spread mortar over the sand before laying the rocks and fill in the gaps between the rocks in the ditch with mortar. If you are building a wall shorter than 2 feet that doesn't need to support weight, you can dry lay the rocks if you choose.

Build the rock wall upward by placing rocks in spots where they fit the best. The process is much like piecing together a puzzle, and you will get the best results if you take time to fit rocks with the proper shape into spots where they fit. As you build upward, spread a 1-inch layer of mortar between the rocks as you place them and use more mortar in areas where it is necessary to fill in extra space.

Make the wall as level on top as possible by fitting rocks into the spaces just as you did for the rest of the wall. Put the smooth side of each rock facing upward if you want the rock to serve as an impromptu garden seat.