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This is so that the top layer seams are offset with the bottom layer. You want each layer of blocks to be different from the one below it. For example, if the wall has straight edges on the ends, the next layer should start with a block that has been cut in half.  Place the blocks onto the foundation before applying the adhesive. See how they look; ask yourself whether you need to make any significant cuts before gluing . Lay out one whole row before moving on to the next step. If you're working with blocks that have flanged tongues, simply line up the female groove of the top block with the male groove of the bottom block. Next, fit the top block overhead. Press down to make sure that each layer is secured tightly against the layer beneath it. Continue until retaining wall is its preferred height. If your wall is over 3 ft (.91 m) in height, you should offset each new row slightly back from the row below it, like very shallow stair steps. This will make your wall more stable and help create a better hold with the soil once you backfill. Look for a perforated pipe and lay it down the length of the retaining wall, covering it up with breathable backfill. Make sure water can drain out of your pipe, either at the ends or through an outlet in the middle of the wall. Topper stones usually come in rectangular shapes, making them more difficult to install in curved retaining walls. If you need to cut topper stones to fit the curve in your retaining wall, follow this trick:  Lay stones #1 and #3 out in their pattern. Lay stone #2 on top of #1 and #3, drawing lines on #1 and #3 where stone #2 overlaps them. Cut stones #1 and #3 along those lines. Line up #1 and #3 into place, snugging #2 in between. Repeat, placing stone #4 on top of stones #3 and #5. Add plants, vines, or flowers as necessary. Your retaining wall is ready to be enjoyed.

Summary:
Start your second layer with a staggered pattern. Apply the recommended adhesive to the bottom blocks, once a layer has been provisionally laid out. Add drainage pipes to your retaining wall, if the wall is 2 feet (60 cm) or taller. Add topper stones, if desired. Place topsoil in the basin created by the retaining wall.