i.e., A local favorite, or hThis is a landscape contractor. They a licensed to plant plants, not to build retaining walls. Always hire a Masonry Contractor to do your masonry project. This helps reassure that you are buying the best for your hard earned $. To advertise that you build retaining walls or anything related to doing masonry, the contractor must have a C29 license not a C27 license. Go to CA Contractors License Board website and check it out for yourself. You wouldn't hire a nose, ears and throat doctor to do your dental work.ighly recommended because