Test fit and lay out each piece of stone veneer against the wall. If needed, cut pieces to size with a circular saw equipped with a masonry blade. Use whole pieces towards the top of the wall and make every attempt to keep cut pieces along the bottom row where shrubs and plants will hide the cuts.
Mix mortar per the instructions on the mortar packaging. Mix in a small amount of quick-set concrete to help speed up the curing process. Quickset will also help the veneer adhere to the wall.
Place a ¼-inch to ½-inch layer of mortar onto the back of the first piece of veneer starting at the top corner of the wall. If you plan to use corner veneer, start with the first piece of corner veneer at the top of the wall. Press the veneer onto the wall. Wiggle it slightly to set the mortar in place.
Mortar the second veneer in the first row and place it against the wall. Leave a ¼-inch gap between the veneer pieces. Repeat this as you work your way across the first row.
Install the second and each subsequent row in the same manner as you installed the first. However, leave a ¼-inch gap between each piece of veneer in every direction. Wipe off excess mortar before it dries with a wet rag.
Cut the corner out of a grout bag and then fill the bag with fresh mortar. Squeeze the mortar into the ¼-inch gaps between the veneer. Run your finger or a round dowel rod down across each gap to remove excess grout. Wipe the wall clean with a wet rag.