Sisyrinchium californicum 'Yellowstone'
- Position: full sun
- Soil: poor to moderately fertile, reliably moist but well-drained, neutral to slightly alkaline soil
- Rate of growth: average to fast-growing
- Flowering period: June to August
- Hardiness: frost hardy (may need winter protection)
Cheerful, bright yellow, open star-like flowers above clumps of sword-shaped, grey-green leaves. This semi-evergreen, summer-flowering perennial is perfect for a sunny, rock or gravel garden. Best planted in well-drained, neutral to slightly alkaline soil, although short-lived it self-seeds freely.
- Garden care: Lift and divide large colonies in spring. It self-seeds freely, so if you do not want it to spread too quickly, cut off the spent flowers before they set seed.