Western blue-eyed grass Sisyrinchium bellum
Western blue-eyed grass (Sisyrinchium bellum) is an evergreen perennial flowering plant in the Iridaceae family, native to Grassland and open woods of California, Oregon and Baja California. It grows 15–40 cm (6–16 in) tall and 15–30 cm (6–12 in) wide, wants full sun and low water, and is hardy to about -12 °C (10 °F). Space plants about 20 cm (8 in) apart.
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Western blue-eyed grass at a glance
| Type | Perennial flowering plant, evergreen |
|---|---|
| Family | Iridaceae |
| Mature height | 15–40 cm (6–16 in) |
| Mature spread | 15–30 cm (6–12 in) |
| Spacing | 20 cm (8 in) centre to centre |
| Sun | Full sun, at least 5 h of direct sun a day |
| Water | Low; drought tolerance moderate, waterlogging tolerance low |
| Soil pH | 5.5–8 |
| Cold hardiness | About -12 °C (10 °F) once established (roughly USDA zone 8) |
| Heat stress | Likely above about 36 °C (97 °F) |
| Flowering | from about March for 4–9 weeks (northern hemisphere; later in cold climates, earlier in warm ones) |
| Wind tolerance | Moderate |
| Pollinator value | Moderate |
| Edible | Not grown as food |
| Native to | Grassland and open woods of California, Oregon and Baja California |
| Common in gardens of | 🇺🇸 United States, 🇲🇽 Mexico, 🇬🇧 United Kingdom, 🇦🇺 Australia |
Is Western blue-eyed grass toxic?
- People: not known to be toxic
- Cats: not known to be toxic
- Dogs: not known to be toxic
Not known to be poisonous.
If a child or pet may have eaten part of a plant, call a poison centre or vet straight away.
Companion planting: what to grow with Western blue-eyed grass
No well-documented helpful pairing. Group it with plants that like full sun and low water.
Questions about Western blue-eyed grass
- How far apart should I plant Western blue-eyed grass?
- About 20 cm (8 in) apart, centre to centre. A mature plant spreads 15–30 cm (6–12 in).
- Does Western blue-eyed grass need full sun?
- Full sun: at least 5 hours of direct sun a day.
- How much water does Western blue-eyed grass need?
- Low water. Drought tolerance is moderate and waterlogging tolerance low.
- How cold-hardy is Western blue-eyed grass?
- It tolerates about -12 °C (10 °F) once established, roughly USDA zone 8.
- When does Western blue-eyed grass flower?
- From about March for 4–9 weeks (northern hemisphere; later in cold climates, earlier in warm ones).
- Is Western blue-eyed grass poisonous to cats and dogs?
- For cats it is not known to be toxic; for dogs not known to be toxic; for people not known to be toxic. Not known to be poisonous.
- What grows well with Western blue-eyed grass?
- There is no well-documented companion pairing for Western blue-eyed grass. Group it with plants that like the same sun (full sun) and water (low).
Sources and evidence
Evidence grade A (A: strong evidence).
- Plants of the World Online (taxonomy, native range), Royal Botanic Gardens, Kew
- Calscape: California native plants, California Native Plant Society
- Calflora: information on California plants, Calflora (non-profit database), Berkeley, California
Notes and assumptions
- A California native of the chaparral and foothills: it grows through the mild, wet winter and rests in the dry summer, when it should be left unwatered once established.
- Not a grass but a small iris: fans of grassy leaves and starry blue-violet flowers with a yellow eye in spring, closing in the afternoon. It goes summer-dormant in dry places and self-seeds lightly.
Reference values for planning, not horticultural, veterinary or medical advice. Varieties, soils and local climates differ: check with a local nursery or extension service.
Related plants
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- Japanese iris Iris ensata
- Siberian iris Iris sibirica
- Dutch crocus Crocus vernus
- Gladiolus Gladiolus x hortulanus
- Freesia Freesia refracta hybrids
- Montbretia (crocosmia) Crocosmia x crocosmiiflora
- African iris Dietes grandiflora