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Japanese Iris

Iris laevigata (EYE-ris lay-vee-GAY-tuh)

Family: Iridaceae Non-native Herbaceous

Rabbit-Ear or Water Iris is a low maintenance perennial, native to the Far East, and ideal for a spot in the yard that has frequent standing water. In its native environment, it is often found growing in shallow water and prefers marshy and still ponds. It can also be grown in damp soil if conditions are right. This plant differs from other irises in its dependence on water. Germination from seed may be erratic, but once underway, it is easy to grow and will bloom from late spring to early summer and, sometimes, into the fall. Flowers are usually blue, purple or violet and have unique color patterns including some types with predominantly white flowers with blue spots and dark purples bordered with white. For the best flowering, it needs a location with full sun, soils that are acidic, rich, and have 2"-8" of standing water. It will tolerate partial shade and some alkalinity in the soil. It looks great planted in large groups along ponds, or streams or in a damp location in a border or cottage garden. Diseases, Insect Pests, and Other Plant Problems: No significant problems. Watch for slugs and snails.

Source: NC State Extension Gardener Plant Toolbox ↗ NC State Extension Gardener Plant Toolbox, 51 attributes.

How it fits the guild

Guild layer 4 - Herbaceous 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.

Fills a similar niche Iris versicolor Lantana camara 'Miss Huff' Salvia farinacea

Full plant profile

Growing Conditions
Plant type
Bulb; Herbaceous Perennial
Life cycle
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
Clay; High Organic Matter; Loam (Silt)
Soil pH
Acid (<6.0); Neutral (6.0-8.0)
Soil drainage
Frequent Standing Water | Moist | Occasionally Wet
Growth rate
Medium
Maintenance
Low
Canopy layer
4 - Herbaceous
Form & Appearance
Habit / form
Clumping; Erect
Leaf color
Green
Leaf type
Simple
Leaf arrangement
Rosulate
Leaf shape
Acicular
Leaf margin
Entire
Hairs present
No
Leaf detail
Narrow strap-shaped upright leaves with entire margins that are erect. Differs from most Iris in that it lacks the strong midrib of the foliage.
Flower color
Blue; Purple/Lavender; White
Flower value
Good Cut; Showy
Flower form
Head
Flower size
3-6 inches
Flower detail
Showy purple flowers 4 inches wide appear in late spring and last through early summer. They can occasionally rebloom in the fall.
Bloom time
Fall; Spring; Summer
Wildlife & Ecology
Native status
Non-native
Origin
Southern Siberia to Japan
Wildlife value
Flowers attract hummingbirds.
Attracts
Hummingbirds
Food & Medicine

Edibility

Can be toxic to cattle.

Landscape Use
Landscape location
Pond; Riparian
Landscape theme
Cottage Garden; Pollinator Garden; Water Garden
Design feature
Border; Mass Planting
Garden tags
#pollinator plant #nectar plant #blue flowers #hummingbird friendly #cottage garden #showy flowers #flower arrangements #standing water tolerant #spring interest #mass planting #summer interest #purple flowers #deer resistant #border planting #low maintenance #bedding plants #pond margins #fall interest #wet soils tolerant #stream banks #summer flowers #problem for dogs #problem for cats #problem for horses #cutting garden #wildlife friendly #pond #contact dermatitis
Problems & Resistance
Insect problems
Slugs and Snails Found on Flowers and Foliage
Problems
Problem for Cats; Problem for Dogs; Problem for Horses
Resistant to
Deer; Wet Soil
Particularly resistant to
deer damage
Propagation
Seed
Poison severity
Low
Poison parts
Roots; Seeds
Poison symptoms
Salivation, vomiting, drooling, lethargy, diarrhea. Highest concentration in rhizomes
Toxic principle
Pentacylic terpenoids (zeorin, missourin and missouriensin)
Contact dermatitis
No
Toxicity summary
Low severity poison; parts: Roots; Seeds

Planted at Hunnicutt

Nobody’s planted this one yet.