Irish moss, also known as Sagina subulata, is a low-maintenance groundcover that can be used in rock gardens, in the spaces between pavers, along the borders of a path, and even as a substitute for a lawn in areas with minimal foot traffic and limited space. This low-growing evergreen perennial has a lush appearance and mimics moss, but it is actually a member of the carnation family (Caryophyllaceae) and has very different growing requirements than...