Sisyrinchium striatum

Sisyrinchium striatum, also known as striped yellow-eyed grass, is a rhizomatous and evergreen perennial plant. It is a cousin of irises. It is hardy and easy to grow. In summer, it produces narrow stems adorned with pale-yellow star-shaped flowers, streaked with purple, emerging from a clump of narrow, greyish-green leaves. While it tolerates drought well, it appreciates moisture that enhances its beauty. It thrives in sunny locations and well-drained, even poor and slightly calcareous, soils where it readily self-seeds.

Native to Argentina, Brazil, and Chile, Sisyrinchium striatum, also known as Phaoiophleps nigricans, belongs to the Iridaceae family. This upright tufted perennial reaches a height of 50 to 70cm (20 to 28in), a width of 35cm (14in), and has a moderately fast growth rate. Sisyrinchium forms a dense, compact, and spreading clump. In late spring and summer, flattened stems appear among the foliage, bearing 6-petalled, pointed yellow flowers arranged in an open cup around a more intensively coloured throat streaked with purple markings. The reverse side of the petals is striated with brown-purple. 5 to 15 flowers are grouped in whorls along the spikes, each spike capable of bearing up to 120 flowers in a season. Only 1 to 3 flowers are open simultaneously on each whorl. The plant produces an abundance of round, black seeds that germinate easily. Its greyish-green foliage is fan-shaped, grass-like, linear, and evergreen. The floral stems and foliage gradually turn black during the season. This perennial is hardy down to -15°C (5°F) in porous soil.

Plant Sisyrinchium striatum in any moist but well-drained soil, even poor and rocky. It requires a sunny exposure to bloom. A truly attractive and undemanding plant in many respects, it is essential in wild, Mediterranean, or even Asian-inspired gardens due to its sleek forms. It also brightens up rockeries, as well as the surroundings of waterfalls and artificial streams, with its unexpected appearance near the base, popping up here and there to give the landscape a natural look. It pairs well with the grey foliage of wormwoods, Crocosmia x crocosmiiflora 'Emily McKenzie', or Calamagrostis x acutiflora 'Karl Foerster'. This perennial is suitable for rockeries, containers, borders, waterfalls, streams, banks, flower beds, or lagoons.