Lyme grass has stunning steel-blue leaves that are ideal for flower arrangements. The leaves of this grass, which is native to Northern Europe, are used for basket weaving, roof thatching, and paper production. Lyme grass attracts butterflies and is used as ground cover and can be grown as a container plant.
I. Appearance and Characteristics
Leymus arenarius is a psammophilic (sand-loving) species of grass in the family Poaceae, native to the coasts of Atlantic and Northern Europe. Leymus arenarius is commonly known as sand ryegrass, sea lyme grass, or simply lyme grass.
Leymus arenarius originated from the hybridization of L. racemosus and another unknown species in central Eurasia or from a polyploidization event. DNA analysis shows that inland and coastal plants are statistically not different from each other. L. arenarius is a recent cultivar, and has had little time to accumulate genetic differences. Leymus arenarius is much younger than its North American relative L. mollis, which has been around since the ice age. Icelandic L. arenarius is molecularly uniform. Polish L. arenarius is also reported to be molecularly uniform.
Noted for its incredibly beautiful blue-gray foliage, Leymus arenarius (Blue Lyme Grass) is a vigorous, semi-evergreen grass that grows in densely tufted, spreading clumps of gracefully arching, broad and flat, steel-blue leaves. In summer, it produces sturdy, upright, narrow, blue-gray flower spikes that turn light beige. Spreading aggressively by rhizomes, this grass needs to be used in very specific situations as it is an aggressive grass. Perfect for erosion control or as a groundcover in a wide sunny area, Blue Lyme Grass makes a good container plant where its invasiveness can be contained.
II. How to Grow and Care
Sunlight
Lyme grass thrives best in environments where it can receive full sun exposure, suggesting that it prefers intense and direct sunlight to reach its full growth potential. While lyme grass is adaptable to some degree and can tolerate partial sun, deviations from full sun might result in suboptimal growth and vitality. In outdoor settings, lyme grass should be planted in open areas where daylight is abundant for the majority of the day.
Due to its preference for full sunlight, lyme grass is equipped with adaptive traits such as robust leaves that can withstand intense light without suffering from damage. Location-wise, lyme grass is more suited to outdoor landscapes rather than indoor cultivation.
Watering
Originating from the sandy soils of coastal regions, lyme grass is well-adapted to environments with moderate moisture. This species thrives in conditions that mimic its native seaside habitat, displaying a preference for consistent but not excessive watering, aligning with its evolutionary adaptations to prevent saltwater saturation. Watering every week will maintain its health and vigor. As an outdoor plant often exposed to the elements, lyme grass has developed robust root systems capable of extracting water efficiently during dry spells, making it a resilient choice for xeriscaping or beachside gardening.
Soil
This grass tolerates a wide range of soils from wet to dry and its tends to be less invasive in dry, clay soils.
Fertilizing
Nourish lyme grass with mulch or compost annually for robust growth. Apply a 2-inch layer around lyme grass, avoiding direct contact with stems to prevent rot. This organic matter slowly releases essential nutrients, enriching soil structure and water retention. Adjust amounts with growth stages—more as lyme grass matures. Seasonal variations necessitate less in dormancy; increase before active growth resumes. Always water lyme grass after applying to assist nutrient uptake. For safety, use gloves and avoid over-fertilization to prevent nitrogen burn.
Propagation
Lyme grass is a vigorous perennial grass well-suited to sandy soils and coastal regions. Its robust rhizomatous nature favors propagation through division. To propagate, carefully separate the plant’s roots during its growth phase to minimize stress. Choose healthy clumps with several shoots and intact root systems for replanting in well-drained soil, ensuring adequate space for spread. Regular watering post-division will support establishment, although lyme grass is generally drought-tolerant once mature.
Transplanting
Transplant lyme grass during the season’s gentle awakening or when the first green whispers emerge, ensuring robust growth. Select a sunny, well-drained spot, and if transplanting groups, space them amply to accommodate their spirited spread.
III. Uses and Benefits
In Europe, the plant’s stems are used for roof thatching and can be woven into a coarse fabric. Seeds have provided food in the past. Beginning as early as the 18th century, the plant’s extensive network of roots was used in stabilizing sands on northern coastal beaches. In Iceland, the grass was harvested as a wild grain as early as the 12th century.
