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Blue Iris

Iris spuria (EYE-ris SPUR-ee-ah)

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

Blue Iris (also commonly known as Salt Marsh Iris or Butterfly Iris) is a 5-foot tall, beardless, herbaceous perennial bulb native to Europe, Africa, and Asia. It is one of the tallest of the iris family. The genus is named for the Greek goddess of the rainbow and the epithet, Spuria, means false. Blue Iris grows best in rich, well-composted, medium moisture, neutral to slightly alkaline, well-drained soils. For best flowering and disease resistance, site the plant in full sun, although it will tolerate light shade. Provide consistent moisture during growth periods, but avoid wet soils. Amend heavy clay soils and avoid overhead watering. Raised plantings are another solution. Deadhead individual spent flowers and remove flowering stems to the ground after bloom. Divide plants immediately after flowering when overcrowding occurs. It typically grows in clumps with attractive 4-foot-long leaves and flowers that display a range of colors from bluish-purple, white, blue, purple, wine and brown. Use blue iris in borders or mass planted in butterfly or cutting gardens. Diseases, Insect Pests, and Other Plant Problems: Good soil drainage is essential to combat potential soft rot problems. Insect problems include iris borer, iris weevil, slugs, snails, thrips, whiteflies and verbena bud moth. Major disease problems include bacterial soft rot, crown rot fungus, rhizome rot, and fungal leaf spot. Watch for mottling of leaves and flowers which may indicate the presence of mosaic virus. Mustard seed fungus can be fatal. Good sanitation practices can often prevent problems.

Source: NC State Extension Gardener Plant Toolbox ↗ NC State Extension Gardener Plant Toolbox, 61 attributes.

How it fits the guild

Guild layer 4 - Herbaceous (3-15 ft) Optimal soil pH 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.

Fills a similar niche Chrysanthemum x morifolium Iris x germanica Narcissus

Full plant profile

Growing Conditions
Plant type
Bulb; Herbaceous Perennial
Life cycle
Bulb; Perennial
USDA zones
5a, 5b, 6a, 6b, 7a, 7b, 8a, 8b, 9a, 9b
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
High Organic Matter
Soil pH
Neutral (6.0-8.0)
Soil drainage
Good Drainage
Available space
12 inches-3 feet
Mature size
Height: 2 ft. 0 in. - 5 ft. 0 in. | Width: 2 ft. 0 in. - 3 ft. 0 in.
Growth rate
Medium
Maintenance
Medium
Canopy layer
4 - Herbaceous (3-15 ft)
Form & Appearance
Habit / form
Clumping; Erect; Spreading
Texture
Medium
Leaf color
Blue; Green
Leaf type
Sheath
Leaf shape
Lanceolate; Linear
Leaf margin
Entire
Leaf value
Showy
Leaf size
> 6 inches long, 1-3 inches wide
Hairs present
No
Leaf detail
Slender, elongated, narrow linear leaves to 3 to 4 feet long. After the plant has flowered and set seed, the leaves die in the late summer.
Flower color
Blue; Purple/Lavender; Red/Burgundy; White
Flower value
Long Bloom Season; Showy
Flower shape
Lipped
Flower size
3-6 inches
Flower detail
Two to five inch flowers typically have bluish-purple segments with falls sometimes having a yellow ridge. Color variations include white, blue, purple, wine and brown. Blossoms May to July.
Bloom time
Spring; Summer
Fruit color
Brown/Copper
Fruit type
Capsule
Fruit detail
After the iris has flowered, it produces an oblong-ovate, hexagonal, seed capsule with a long beak-like appendage on the top and 6 visible, longitudinal groves. Inside the capsule, are light brown, angular seeds.
Stem detail
Stems typically rise to 3 feet (occasionally to 5 feet) tall. Stalk height is often reduced in cold winter climates.
Wildlife & Ecology
Native status
Non-native
Origin
Europe, northern Africa, southwestern Asia
Distribution
California
Wildlife value
Flowers attract butterflies
Attracts
Butterflies
Food & Medicine
Harvest time
Fall
Fruit type
Capsule

Edibility

Can be mildly toxic if ingested.

Landscape Use
Landscape location
Small Space
Landscape theme
Butterfly Garden; Cutting Garden
Design feature
Border; Mass Planting
Garden tags
#showy flowers #blue flowers #problem for cats #problem for dogs #problem for horses #long bloom time #bulb #tall #multicolored #butterfly friendly #contact dermatitis #cutting garden #mass planted #border #cut flower
Problems & Resistance
Insect problems
Slugs and Snails Found on Flowers and Foliage; Narcissus Bulb Fly; Potato Aphid on Ornamental Plants
Problems
Problem for Cats; Problem for Dogs; Problem for Horses
Propagation
Division
Poison severity
Low
Poison parts
Leaves; Roots; Sap/Juice
Poison symptoms
Salivation, vomiting, drooling, lethargy, diarrhea. Highest concentration in rhizomes. Can cause skin irritation.
Toxic principle
Pentacylic terpenoids (zeorin, missourin and missouriensin)
Contact dermatitis
Yes
Toxicity summary
Low severity poison; parts: Leaves; Roots; Sap/Juice; contact dermatitis

Planted at Hunnicutt

Nobody’s planted this one yet.