Curving borders add visual interest and softer, more natural contours to a garden area. But the benefits of serpentine masonry garden walls are not only aesthetic, but practical as well. When the degree of curvature is sufficient, the shape of serpentine walls increases their lateral stability. Thus they often can be built of a single wythe of masonry, without piers or reinforcement. SERPENTINE WALL PROPORTIONS Serpentine single-wythe brick walls 4 inches thick and up to 4 feet 8 inches tall can be designed using rules of thumb derived from the observed performance of successful walls. Empirical design guidelines for a serpentine concrete masonry wall allow wall heights up to 15 times the wall thickness. FOUNDATIONS AND CAPS Foundations for garden walls may be poured concrete, or brick or concrete block that is durable enough for below-grade use. All garden walls should be capped to provide a finished appearance and reduce water infiltration from the top. DURABILITY Although garden walls are not required to form a weather barrier, their extreme exposure makes durability important.