Ground covers, such as those in the genus Liriope, provide an aesthetically appealing feature to landscapes, where they are often used as low-maintenance alternatives to turfgrass species or as a landscape bed border. Common names for Liriope include big blue lilyturf, border grass, or more simply, lilyturf. While similar in appearance to grasses, Liriope are, in fact, not a grass species but instead a member of the asparagus family (Asparagaceae); however, it was formerly classified as part of the lily family (Liliaceae), hence the etymology of its common name. Native to Asia, there are two species of Liriope that are commonly used in the southern landscape, providing a range of attributes to select from depending on the site conditions, specific cultivar, and the desires of the landscape designer.

Liriope muscari: Noted for its clumping form, L. muscari is a popular choice for the landscape with its rapid growth habit and showy, light purple flower blooms in late summer and early fall. Maintaining a modest height, this species tops out around 1.5 feet, with a spread of around 1-2 feet. Clumps of L. muscari spread moderately through surface stolons and do not have the comparatively aggressive spreading nature of L. spicata; however, the dense evergreen foliage, consisting of gracefully arching, glossy leaves (approximately 1 inch in width) provides a desirable, manageable feature in the landscape.

Liriope spicata: The aggressively spreading habit of L. spicata may be considered a prized feature (if desiring rapid coverage of a large area of ground) or a challenge to tame. Similar in height to L. muscari, albeit slightly shorter with a height of 0.75-1.5 feet, the spreading habit extends over a large area if not controlled. The spreading habit is spurred by subsurface rhizomes, giving way to evergreen foliage similar in appearance to L. muscari, just at a narrower width (typically up to ¼-inch wide).

While these two are quite similar, several key distinguishing features separate these two Liriope species besides their growth habit. For L. muscari, the height is slightly taller, and the leaves are slightly wider than L. spicata. Flowers of L. muscari are slightly larger and have a deeper coloration (generally lavender) than L. spicata. The ideal use of these plants also varies, primarily with regard to the spread. When using Liriope as a border plant, outlining a landscape bed, or creating a defined line, select the less aggressive spreader (muscari) to create an easy-to-maintain, crisp line. Conversely, if rapid coverage of a large area is desired, perhaps as an alternative to turfgrass in hard-to-maintain areas, selecting L. spicata may be preferred.

Parking lot island using Liriope to create a dense, turf-like plot amidst a concrete jungle. Photo by Damon Abdi

Purple flowers and variegated foliage found in Liriope varieties offer added interest to the landscape. Photo by Damon Abdi

In general, Liriope performs well across a spectrum of environmental conditions ranging from full sun to part shade and in well-drained soils that retain sufficient moisture. In brighter conditions, the blooms are more profuse. For each species, there are several cultivars offering unique features to further enhance the landscape, such as variegated leaves, different flower colors and variations in morphology (i.e. size and density). Pruning or cutting back in late winter to remove overgrowth and dead foliage is recommended to clean up the plant before new growth begins in spring.

For more information on ground covers, please contact your local LSU AgCenter Extension office or visit www.LSUAgCenter.com