Iris sibirica /ˈiː.rɪs/
Common name: Siberian iris · Siberian flag
Iris sibirica is a herbaceous perennial in the iris family, native to a broad area from central Europe through Russia to Central Asia. It forms clumps of slender, grass-like foliage and bears elegant, beardless flowers in early summer, most often in shades of blue and violet. Unlike bearded irises, it tolerates moist soils and needs little division. It is widely grown in borders and waterside plantings and is the parent of many hardy garden hybrids.
Care summary
Sun
Full sun to partial shade
Water
Moderate; likes consistently moist soil
Soil
Moist, humus-rich, slightly acidic
Hardiness
Zones 3–9
Mature height
About 60–120 cm (2–4 ft)
Pet safe
No; mildly toxic to cats and dogs if eaten
Difficulty
Easy
Propagation
Clumps are divided in early spring or just after flowering. Lift the plant, split it into sections with several shoots and roots using a sharp knife or spade, and replant promptly at the same depth, keeping them well watered while they settle. Seed is also viable but takes several years to reach flowering size.
Fun facts
- Despite the name, Iris sibirica is native as much to central Europe as to Siberia, where it grows in damp meadows.
- Siberian iris clumps can thrive undisturbed for decades and resent being divided, unlike bearded irises.
- Its flowers lack the fuzzy "beard" of Iris germanica, placing it in the beardless iris group.
- The narrow foliage stays attractive all season and turns bronze-gold in autumn.