Many different types of materials can be used to build small walls. Not to mention retaining walls for outdoor landscaping and gardening. Numerous companies build all sorts of specialty products for these solutions. Landscaping retaining walls can help separate different areas of your yard. The benefit in working with these types of products is that they can be simply stacked on top of each other. This can be done quickly without mortar or concrete being used. After they are all stacked together, no paint are needed as they are very decorative all by themselves.