Sisyrinchium angustifolium
narrow-leaved blue-eyed grass
A semi-evergreen perennial to 50cm, producing clumps of narrow, dark green, grass-like foliage and upright stems bearing deep blue, yellow-throated flowers 2cm across all summer
Size
Ultimate height
0.1–0.5 metresTime to ultimate height
2–5 yearsUltimate spread
0.1–0.5 metresGrowing conditions
Moisture
Well–drainedpH
Alkaline, NeutralColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | Green | |||
|---|---|---|---|---|
| Summer | Blue Yellow | Green | ||
| Autumn | Green | |||
| Winter | Green |
Position
- Full sun
Aspect
South–facing or West–facing
Exposure
Exposed or Sheltered Hardiness
H5Botanical details
- Family
- Iridaceae
- Native to GB / Ireland
- No
- Foliage
- Semi evergreen
- Habit
- Clump forming, Tufted
- Genus
Sisyrinchium can be annuals or rhizomatous perennials forming a clump of narrowly sword-shaped leaves with erect stems carrying solitary or clustered, star-shaped or bell-shaped flowers in spring or summer
- Name status
Unresolved
- Plant range
- E Canada to C & E USA
How to grow
Cultivation
Grow in poor to moderately fertile, well-drained, neutral to slightly alkaline soil in full sun. Protect from excessive winter wet. May have the potential to become a nuisance as seeds prolifically
Propagation
Propagate by seed, or by division in spring. Self-seeds readily
Suggested planting locations and garden types
- City and courtyard gardens
- Cottage and informal garden
- Patio and container plants
- Rock garden
- Flower borders and beds
- Garden edging
Pruning
No pruning required
Pests
Generally pest-free
Diseases
May be susceptible to root rot
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