Iris setosa

Common Names

Alaska Iris, Beachhead Iris, Bristle-Pointed Iris, Wild Flag Iris, Arctic Iris

Summary

An herbaceous, rhizomatous perennial forming dense clumps with stiff, sword-like leaves 30–60 cm long; reaches 60–90 cm in height and bears up to 13 flowers on stout stems. Flowers are blue to purple-blue, about 6–9 cm wide, with standards reduced to a bristle and large heart-shaped falls that are deeply veined with a yellow-white signal; bloom occurs in late spring to early summer. Native to North America (Alaska, Yukon, British Columbia) with coastal distribution, distinctive bristle-like standards and contrasting signal.

Prefers full sun to partial shade and wet to mesic, neutral to slightly acidic loam; deer resistant and tolerant of wet soil; suitable for beds, borders, bog/rain gardens, ponds, streams. Propagation by seed (autumn/spring) or division of rhizomes (midsummer–early autumn); hardy in zones 3–8; all parts may cause discomfort if ingested; rhizomes may be poisonous.

Lifecycle

Perennial

Height

12 inches to 3.5 feet

Spread

1-2 feet

Hardiness Zones

Zones 3-8

Sunlight Requirements

Ideally full sun to partial shade.

Soil Type

Moist, well-drained loam or humus-rich soil with pH 5.5–7.0; not lime-rich/alkaline.

Soil Drainage

Well-drained, moist to mesic soil; avoid waterlogged conditions.

Soil pH

6.0-7.0, Slightly acidic to neutral soil

Bloom Color

Blue to purple (violet, purple-blue, blue, lavender)

Bloom Time

Spring to Summer

Foliage Color

Green, often mid-green, sometimes tinged with purple at the base.

Fall Foliage Color

Green, purple-tinged at the base.

Leaf Lifecycle

Deciduous

Growth Rate

Average; reaches ultimate height in 2–5 years; spreads slowly via rhizomes, forming large clumps.

Seasons of Interest

Spring, Summer, Fall, Winter

Propagation Methods

Seeds and Division

Attracts Wildlife

Attracts bees, hummingbirds, butterflies, and other pollinators