Sisyrinchium angustifolium or Blue-Eyed Grass looks rather like regular grass until the flowers emerge, then it becomes something far more interesting.
The foliage of this clump forming, herbaceous perennial is green, upright and narrow and the flowers appear on stalks in clusters of violet-blue with prominent veins.
The flowers have six pointed tepals and a yellow centre and make a pretty, low growing display that can be useful as a ground cover or to line pathways.
They also suit rockery planting and any informal or cottage style garden, especially larger gardens with some open woodland areas.