Steep hillsides, because of their nature, are often times very hard to manage. Terracing can improve the safety of a slope while adding an aesthetic and economic value to a property.
Taking your slopes and turning them into something extraordinary with beautiful gardens and planting areas can be accomplished with building multiple walls. Think of a terraced slope as building very large steps up a hill. Each of these new steps can be created to be planting areas. This will add a softer look to a hillside and allows rainwater to soak into the hill watering the plants instead of just running down the slope.
Terraces should be properly built and constructed to ensure a lifetime of use. Multiple walls will act as surcharges on the bottom walls so an engineering review is recommended. Water runoff or draining down the wall improperly will also need to be evaluated as heavy wet soil will cause erosion or worse; a possible wall failure.
A general rule of thumb when building terraces is if the distance between the walls is less than two times the height of the lower wall, the upper wall could be putting pressure on the lower wall and reinforcement may be necessary.
When the need arises where a large wall is needed to retain a slope, consider making it a terrace by adding multiple walls. Then add in a flowing stairway to elevate your architectural style and add even more visual appeal.