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Siberian Flag

Iris sibirica (EYE-ris sy-BEER-ah-kuh)

Family: Iridaceae Non-native Herbaceous (3-15 ft)

Siberian Iris is an easy to grow, medium tall, clumping, low maintenance, versatile perennial that is native to Central and Eastern Europe. Its showy flowers, interesting seed pods and bluish green strappy foliage make this a wonderful specimen plant. Siberian Iris generally blooms in shades of bluish-purple; however some of its cultivars have been introduced in white, pink, orange, red, and yellow. The word iris translates to the goddess of the rainbow in Greek mythology. Through history, its blooms have been a symbol of monarchs and royal families. The flower's shape is the inspiration for the french 'fleur-de-lis'. Siberian Iris typically reaches a height of 2 feet, although some cultivars can be taller. Flowering profusely, clumps can produce 12 to 20 flowers. It is a moisture loving plant, and will thrive near a stream or edge of a pond, wherever soil is evenly moist. Well established plants will tolerate some drought. Grow in full sun. Shade can have an effect on the plants performance. Too much shade may cause the plant to lay over and flowers to produce fewer blooms. In the southeast, protect from hot afternoon sun. Siberian Iris tolerates a wide variety of soils, but will perform best when grown in moist fertile, organically rich, slightly acidic, well drained soils. Divide the plants about every three years, or once the plants become over crowded and fewer blooms appear. Growing from rhizomes that will spread, over time your iris will form a beautiful clump of blooms. They are perfect for cutting and including in an arrangement. When the clumps become too large, they can be easily divided. Remove the rhizomes from the garden by gently loosening the surrounding soil. Rocking the plant back and forth will help protect the rhizome from damage during removal. After cutting back to 6 to 8 inches, each clump can be cut with a sharp knife. Ensure that each division contains at least two fan division Plant each division, cover with 1 to 2 inches of soil and keep moist for 6 to 8 weeks. The best planting time for the southeast is fall. Plant in the spring in cooler winter areas. It may take more than one season for the plants to bloom, but planting in the fall will give them a head start. Siberian Iris bloom best after a cold period in winter. A lack of cold period may reduce blooms and the plant's ability to produce new bulbs. In USDA hardiness 8b and above, warm winters may hinder these blooms. Until established, this plant prefers consistent moisture. It tolerates drought after it has been established in one or two seasons. This plant is less prone to pests and diseases of other Irises. Insects, Diseases, and Other Plant Problems: Occasional issue can occur, such as bacterial soft root. Slugs and snails may can cause damage, however, they too are not a persistent problem. Wear gloves when handling this plant as the sap can cause skin irritation.

Source: NC State Extension Gardener Plant Toolbox ↗ NC State Extension Gardener Plant Toolbox, 68 attributes.

How it fits the guild

Guild layer 4 - Herbaceous (3-15 ft) Optimal soil pH Acid (<6.0); Neutral (6.0-8.0)
See companions & conflicts ↓

Companions & Conflicts

Curated pairwise relationships between this plant and others in the library — who feeds whom, who competes, who confuses the pests. Green reads as a good pairing, red as one to avoid.

No curated interactions recorded for this species yet.

Also noted by NC State

Related species the NC State Plant Toolbox flags for this plant — look-alikes to tell apart, and plants that play a similar role in a planting. Ones we carry in the library are linked.

Often confused with Iris ensata
Fills a similar niche Buddleja 'Miss Molly' Buddleja 'Miss Violet' Erigeron

Full plant profile

Growing Conditions
Plant type
Bulb; Herbaceous Perennial; Perennial
Life cycle
Perennial
USDA zones
3a, 3b, 4a, 4b, 5a, 5b, 6a, 6b, 7a, 7b, 8a, 8b
Light
Full sun (6 or more hours of direct sunlight a day) | Partial Shade (Direct sunlight only part of the day, 2-6 hours)
Soil texture
Clay; High Organic Matter; Loam (Silt); Sand
Soil pH
Acid (<6.0); Neutral (6.0-8.0)
Soil drainage
Good Drainage | Moist | Occasionally Wet
Available space
12 inches-3 feet
NC region
Coastal; Mountains; Piedmont
Mature size
Height: 2 ft. 0 in. - 4 ft. 0 in. | Width: 2 ft. 6 in. - 3 ft. 0 in.
Growth rate
Rapid
Maintenance
Low
Canopy layer
4 - Herbaceous (3-15 ft)
Form & Appearance
Habit / form
Arching; Clumping; Erect
Texture
Medium
Foliage
Deciduous
Leaf color
Blue; Green
Leaf type
Simple
Leaf arrangement
Alternate
Leaf shape
Linear
Leaf margin
Entire
Leaf value
Showy
Leaf size
> 6 inches long, < 1 inch wide
Hairs present
No
Leaf detail
Ribbed grassy leaves can range from 10 to 30 inches long, while the width rarely exceeds 1 inch. Leaves grow at the base of the plant. The leaves are shorter than the flowers stems. Arching leaves form a vase-like clump of foliage
Fall color
Brown/Copper
Flower color
Blue; Brown/Copper; Gold/Yellow; Orange; Purple/Lavender; Red/Burgundy; White
Flower value
Long Bloom Season; Showy
Flower form
Head; Solitary
Flower shape
Tubular
Flower size
1-3 inches
Flower detail
The flowers have 2 pairs of petals consisting of 3 large outer sepals and 3 inner tepals. Siberian Iris are available in white, yellow, blue, wine, and purple. The soft looking flower bloom is divided into six sections, three upright petals (standards) and three lower outer petals (falls) which are beardless. The falls of the Siberian Iris are marked with white or gold flashes which begin from the inner petal and go to mid petal. The flowers tend to be smaller than those of bearded Iris varieties.
Bloom time
Spring; Summer
Fruit type
Capsule
Stem detail
The erect stems rise above the leaves and each can have 2 t0 5 flowers.
Wildlife & Ecology
Native status
Non-native
Origin
Hybrid of two Asian species
Distribution
Central Europe,Russia, Japan, Korea
Wildlife value
Butterflies are attracted to the flowers.
Attracts
Bees; Butterflies; Pollinators
Play value
Attractive Flowers; Attracts Pollinators; Buffer; Colorful; Easy to Grow
Food & Medicine
Fruit type
Capsule

Edibility

The rhizomes are not edible.

Landscape Use
Landscape location
Coastal; Container; Meadow; Patio; Pond; Pool/Hardscape; Slope/Bank; Small Space; Walkways
Landscape theme
Butterfly Garden; Cottage Garden; Cutting Garden; Drought Tolerant Garden; Pollinator Garden; Rain Garden; Rock Garden
Design feature
Accent; Border; Mass Planting; Small groups; Specimen
Garden tags
#rabbit resistant #long bloom time #herbaceous #wet soils tolerant #cutting garden #showy flowers #herbaceous perennial #clay soils tolerant #drought tolerant #deer resistant #butterfly friendly #dry soils intolerant #deciduous #pollinator plant #HS304 #contact dermatitis #th-touch #th-sowing #wildlife friendly
Problems & Resistance
Insect problems
Slugs and Snails Found on Flowers and Foliage
Resistant to
Black Walnut; Deer; Diseases; Drought; Insect Pests; Poor Soil; Rabbits; Wet Soil
Propagation
Division
Fire risk
low flammability
Poison severity
Low
Poison parts
Roots; Sap/Juice
Poison symptoms
Ingesting rhizome or root stock can cause stomach pain and vomiting. Contact with sap can cause skin irritation.
Toxic principle
Unidentified, possibly a glycoside
Contact dermatitis
Yes
Toxicity summary
Low severity poison; parts: Roots; Sap/Juice; contact dermatitis

Planted at Hunnicutt

Nobody’s planted this one yet.