Siberian iris is a hardy perennial that brings cool-season elegance to gardens across zones 3 through 8. Born from hybrid origins tracing back to two blue-flowered Asian species, Iris sibirica and Iris sanguinea, this variety forms graceful arching clumps of narrow, grass-like blue-green foliage that reach 24 to 36 inches tall. In May and June, flowering stems rise above the foliage bearing 2 to 5 blooms in shades of blue and lavender, each stem reaching up to 3 feet. These flowers are prized for cutting and command attention in any garden setting. Beyond ornamental appeal, Siberian iris tolerates clay soil, wet conditions, drought, and erosion with equal composure, thriving where other plants struggle.
Partial Sun
Moderate
3-8
36in H x 30in W
—
Low
Hover over chart points for details
Arching blue-green foliage creates a vase-shaped clump that stays attractive long after flowers fade, and the delicate blue and lavender blooms make exceptional cut flowers that last well in arrangements. Unlike bearded irises, Siberian iris shows remarkably little susceptibility to iris borer or bacterial soft rot, meaning you can grow it reliably without the fussy maintenance those cousins demand. This variety handles wet boggy soils as easily as dry ones, truly earning its reputation as an adaptable garden workhorse.
Siberian iris shines as a specimen plant in rain gardens and wetland areas where its tolerance for fluctuating moisture levels prevents erosion and manages stormwater. The showy blue and lavender flowers are excellent for cutting, bringing a delicate, refined aesthetic to indoor arrangements. In the landscape, it attracts butterflies and serves as a low-maintenance focal point in perennial borders, particularly where traditional bearded irises prove temperamental.
No timeline data available yet for this variety.
Transplant seedlings outdoors after the last frost date in your region. Harden off gradually over 7 to 10 days by exposing plants to increasing amounts of outdoor conditions before planting. Space transplants 6 inches apart, with 12 inches between rows.
For cut flowers, harvest stems in the early morning when blooms are fully open or just beginning to open. Cut stems at ground level using sharp shears and immediately place them in cool water. Siberian iris flowers typically last 7 to 10 days in a vase, making them reliable for arrangements.
Remove spent flower stems after blooming concludes in late June to redirect energy into foliage and root development. Divide established clumps every 3 to 4 years in early spring or fall to maintain vigor and prevent overcrowding. Cut back dead or winter-damaged foliage in early spring as new growth begins.
Enter your ZIP code to see a personalized growing calendar for this plant.
“Siberian iris represents a triumph of plant hybridization drawn from two wild Asian species with remarkable geographic range. Iris sibirica, native to central Europe, northeastern Turkey, and southeastern Russia, was crossed with Iris sanguinea, which ranges across Russia, Korea, and Japan, to create the hybrid group now known as Siberian iris. These crosses were deliberately developed to combine the hardiness and aesthetic qualities of these two blue-flowered parents into garden-worthy plants that could thrive across temperate climates.”