Stone walls add beauty and form to your gardens and outdoor yards. A mortared stone wall is strong and stable, adding the feel that it's been there for years. Building a mortared stone wall is a great do it yourself project for the homeowner. If you have a good eye and can work with precision and patience, then a mortared stone wall is the perfect project.
Determine the wall location. This is done by using landscape-friendly spray paint or lime to outline the "footprint" of the mortared stone wall you want to build. Use the landscape friendly spray paint to mark directly on the ground where you want the stone wall to be. Push sticks into the ground at the very ends of the stone wall; make sure the sticks are at least as tall as the wall will be.
Attach a string to one stick at the exact height of the finished wall, stretch the remaining string down to the other stick and attach it to the stick, again at the exact height you want the finished stone wall to be. The string will help you "eyeball" the wall and keep it level.
Prepare the foundation of the wall. Dig out a trench that is at least as wide as the size of a large stone and at least 30 cm (1 foot) deep. The taller the stone wall you build, the deeper the trench needs to be; 30 cm (1 foot) deep is adequate for a 1.2 m (4 foot) tall wall. Fill the trench almost to ground level with gravel, leaving about a 5 cm (2 inch) difference.
Using the larger stones (even damaged ones), lay them on top of the gravel for a "dry run." You are merely placing the stones to see how they fit together and find the most stable and flat stones for the bottom course. When you are satisfied, place the stones behind the foundation to be mortared, directly behind where they will be set in mortar. This helps you keep track of which stones go where. Save some large stones in excellent shape for the top course of the wall for a finished look.
Mix the mortar in a wheelbarrow or large 22.5 litre (5 gallon) bucket. Make sure you follow the package instructions to get a good mix. Most people use Ready Mix as the mortar; all you do is add water to the Ready Mix and mix to the consistency that it slides off the trowel.
Plop a large dollop of the mortar onto the gravel and set the first stone. Gently push on the stone to make sure it is securely seated. Continue setting stones across the length of the wall using the same technique. Use a level to keep the courses straight and add more mortar if needed. "Dry" set the second course to find the right stones and place them directly behind where they will be set. Remember to stagger the joints as you set them.
Continue setting the stones in mortar, going from left to right or vice versa. Setting stones horizontally keeps the lines clean and the joints staggered. Staggered joints add strength and beauty to the stone wall. Use the previously saved, large stones for the top course of the stone wall.
Clean the excess mortar and drips from the stone wall before the mortar has set completely; use a stick to remove large clumps of mortar and a brush to clean the surface of the stones after the mortar is almost set but not dry.