Blue-eyed Grass

Blue-eyed Grass © SBernhard

Western Blue-eyed Grass
Sisyrinchium bellum

Description (Jepson,

  • Monocotyledon
    • Monocots are a major lineage of flowering plants; see family for general characteristics
  • Iris Family (Iridaceae)
  • Perennial herb, upright growth habit
    • Grows from rhizomes (underground, horizontal stems)
  • Leaves
    • Basal and alternate (one leaf at each junction with stem)
    • Grass-like, in fan-like sprays that sheathe the stem
  • Flowers
    • Inflorescence (flower arrangement) of 3-5 flowers open sequentially on branching iris-like stalks, about the height of the leaves
    • 3 petals and 3 sepals (outer flower parts), similar in appearance and collectively called tepals
      • Blue-purple, with dark lines (nectar guides) leading to a yellow center
      • Outer edge often with a small point (mucro) projecting from a notch
    • 3 stamens (male flower parts), fused in a column around the pistil (female flower part)
    • Ovary inferior (below the attachment of other flower parts)
  • Fruit is a capsule (a dry, multi-chambered fruit that splits open at maturity)
  • Height 12-18 in.


  • Native to California
    • Grows in open grasslands with some moisture, but also found in woodlands
    • See Calflora for statewide observations of this plant
  • Outside of California, grows from Oregon to Mexico, but confined to western North America
  • Grows at elevations to 7,900 ft.

Uses (San Mateo County Parks prohibits removal of any natural material)

  • Wildlife
    • Nectar and pollen source for insects
  • Native people
    • Decoction used to treat chills and stomach aches
    • Purgative produced from roots
    • Infusion of washed roots taken for upset stomach, heartburn, asthma, and ulcers

Name Derivation

  • Sisyrinchium (si-si-RINK-ee-um) from the Greek sys, “pig,” and rynchos, “snout,” alluding to pigs grubbing the roots for food
    • Theophrastus, a student of Aristotle, first used this name to describe a type of iris (Ritter 2018)
  • bellum (BEL-lum) – Latin for handsome
  • Blue-eyed grass – flower suggests a blue eye with a yellow iris; leaves are similar to grass
    • From a distance, a field of blue-eyed grass can appear spotted with blue eyes
    • Also sometimes called yellow-eyed iris
Seeds © DSchiel


  • Flowers open in the morning and close in the evening or when it’s cloudy
    • This process is an example of nyctinasty, which refers to diurnal and nocturnal changes (single or repetitive) exhibited by the leaves and flowers of some plants (van Doorn 2003)
  • After flowering, the plant dies back and remains dormant through the summer
  • The petals and sepals of plants in the blue-eyed grass genus, Sisyrinchium, look more alike than do those of typical garden irises

ID Tips

  • May be confused when not flowering with iris-leaved rush (Juncus xiphioides), which also has sheathing, linear leaves
    • Iris-leaved rush leaves are hollow, and you can feel bumps from the interior partitions (crosswalls) by running your fingers along the leaf blade
  • Check out this short video (Jepson 2020) for more ID tips

At Edgewood

  • Found in moist grasslands
  • Flowers March – May

See General References

Specific References

Jepson Herbarium. 2020, Jun. 18. Sisyrinchium bellum (Western blue-eyed-grass) [Video]. The Jepson Videos: Visual Guide to the Plants of California. The Regents of the University of California. YouTube.

Ladybird Johnson Wildflower Center. 2009. Sisyrinchium bellum. Plant Database. University of Texas at Austin.

Nature Collective. 2020. Blue-eyed grass.

Ritter, M. 2018. California Plants: A Guide to Our Iconic Flora. Pacific Street Publishing, San Luis Obispo, California.

van Doorn, W.G. and U. van Meeteren. 2003, Aug. 1. Flower opening and closure: A review. Journal of Experimental Botany 54: 1801–1812. Oxford Academic.