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Iris (EYE-riss)

Family: Iridaceae Non-native Herbaceous (1-3 ft)

The Iris is one of the most popular herbaceous perennials and is available in a variety of colors with varying blooming times. The family Iridaceae is a very large one of herbaceous perennials growing from a rhizome, corm, or bulb. There are Iris species native throughout the world that offer the possibility of use in a native or woodland garden. The native habitats of the Iris range from North America, Europe, Africa, and Asia. They grow in meadows, deserts, mountain ranges, hillsides, and along streams. In Greek mythology, Iris is the Goddess of the Rainbow. The genus name, Iris, is from the Greek word for "rainbow' and is aptly named because of the variety of flower colors available. The genus has about 300 species and thousands of cultivars. Different varieties require light from full sun to full shade. Neutral to alkaline soils are required for some species. They grow in mounds or drifts in rich soils; some prefer wet or marshy areas and even standing water. They propagate through root division or by seed. Some varieties require rhizomes to be at soil level, while others tolerate planting corms and bulbs deeper in the soil. Most iris require periodic division of the rhizomes. After blooming is complete, allow the foliage to deteriorate and then remove the spent foliage. The leaves tend to be long, strap-like, and sword-shaped, overlapping at the base, and oriented in one plane. The flowers may be a single to several blooms. They are carried at the top of a naked stem. The stem can be as short as 3 inches in dwarf varieties to as tall as 3 feet. The showy blooms are 6-parted with three often distinctly marked outer, spreading, or pendant "falls" and three inner, erect "standards". The variety of iris colors ranges from blues to violets to yellows to oranges to white to even black and are prized as cut flowers in the perennial garden. The seeds are carried in a fruit capsule, but the division of the rhizome or root is the best propagation method and helps to prevent overcrowding. Iris is most effective when planted in small groups or in mass plantings. They may be used as border plantings, foundation plantings, near a patio, and along walkways, woodlands, and meadows. They are perfect for a cutting garden or cottage garden. Quick ID Hints: green sword-like foliage, basal leaves are commonly fan-shaped, leaves are 2-ranked and often flat. small to large, showy orchid-like flowers in a variety of colors blooms have 3 upright petals known as standards, 3 downward-facing sepals called falls, fruit is a brown capsule Insects, Diseases, and Other Plant Problems: Potential insect pests include aphids, caterpillars, beetles, snails, slugs, spider mites, thrips, and whiteflies. They are susceptible to diseases such as bacterial soft rot, botrytis blight or gray mold, leaf spots, root and crown rots, rust, and viruses. To learn more about individual species, see the boxes below. VIDEO created by Andy Pulte for “Landscape Plant Identification, Taxonomy, and Morphology” a plant identification course offered by the Department of Plant Sciences, University of Tennessee.

Source: NC State Extension Gardener Plant Toolbox ↗ NC State Extension Gardener Plant Toolbox, 63 attributes.

How it fits the guild

Guild layer 4 - Herbaceous (1-3 ft) Optimal soil pH Alkaline (>8.0); 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 Babiana nervosa Gladiolus
Fills a similar niche Convallaria majalis Helleborus orientalis Iris x germanica
Native alternatives Iris cristata Iris virginica

Full plant profile

Growing Conditions
Plant type
Bulb; Herbaceous Perennial; Poisonous
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)
Soil pH
Alkaline (>8.0); Neutral (6.0-8.0)
Soil drainage
Good Drainage | Moist
Available space
Less than 12 inches; 12 inches-3 feet
NC region
Coastal; Mountains; Piedmont
Mature size
Height: 1 ft. 6 in. - 2 ft. 6 in. | Width: 1 ft. 0 in. - 2 ft. 0 in.
Maintenance
Medium
Canopy layer
4 - Herbaceous (1-3 ft)
Form & Appearance
Texture
Medium
Foliage
Deciduous
Leaf color
Blue; Green; Variegated
Leaf type
Sheath; Simple
Leaf arrangement
Rosulate
Leaf shape
Lanceolate; Linear
Leaf margin
Entire
Leaf size
> 6 inches long, 1-3 inches wide
Hairs present
No
Leaf detail
The leaves are green to bluish-green, and blades, swords, or fans of foliage. They have parallel leaf veins. Range in size from 6 inches to 2 feet and are arranged in clumps. Strap-like, overlapping at base, oriented in one plane. Leaves are 2-ranked, linear to ensiform, flat or tetragonal. Basal leaves are commonly in fans. Cauline leaves are sheathing or in an apical tuft.
Fall color
Gold/Yellow
Flower color
Black; Blue; Cream/Tan; Gold/Yellow; Orange; Pink; Purple/Lavender; Red/Burgundy; White
Flower value
Good Cut; Long-lasting; Showy
Flower size
> 6 inches
Flower detail
One to several flowers at the top of a naked stem in bracteate heads. Perianth tubular with 6-parted segments with three pendent "falls" that are narrowed basally into a shaft, are spreading to deflexed above, are bearded or with colored trichomes or crest, or are lacking these traits often with a basal medial color patch. Three inner, erect "standards", variously colored, clawed and reduced. Three stamens, three styles, petaloid, overarching falls.
Bloom time
Spring; Summer
Fruit color
Brown/Copper
Fruit type
Capsule
Fruit size
1-3 inches long, < 1 inch wide
Fruit detail
The fruits is a brown capsule and measures 2 inches long and 1 inch wide.
Stem color
Green
Wildlife & Ecology
Native status
Non-native
Origin
North temperate America, Europe, Asia
Food & Medicine
Harvest time
Fall
Fruit type
Capsule
Landscape Use
Landscape location
Container; Meadow; Naturalized Area; Patio; Small Space; Walkways; Woodland
Landscape theme
Cottage Garden; Cutting Garden
Design feature
Accent; Border; Foundation Planting; Mass Planting; Small groups
Garden tags
#purple #white flowers #purple flowers #bulb #poisonous #pink flowers #rhizomes #orange flowers #yellow flowers #black flowers #rabbit resistant #large flowers #cutting garden #border planting #naturalizes #border front #spring flowers #deer resistant #small spaces #spring flowering bulbs #HS302 #problem for dogs #problem for cats #problem for horses #container plant #corm #landscape plant sleuths course #buncombe county sun and shade garden #cpp #woodland #hortcontest #walkway #contact dermatitis
Problems & Resistance
Insect problems
Slugs and Snails Found on Flowers and Foliage; Aphids on Ornamental Landscape Plants; Narcissus Bulb Fly; Potato Aphid on Ornamental Plants
Problems
Contact Dermatitis; Poisonous to Humans; Problem for Cats; Problem for Dogs; Problem for Horses
Resistant to
Deer; Rabbits
Particularly resistant to
deer and rabbit resistant (in general)
Propagation
Division
Fire risk
low flammability
Poison severity
Low
Poison parts
Roots; Sap/Juice; Seeds
Poison symptoms
CAUSES ONLY LOW TOXICITY IF EATEN. SKIN IRRITATION MINOR, OR LASTING ONLY FOR A FEW MINUTES. Nausea, salivation, vomiting, abdominal pain, lethargy, diarrhea, elevated temperature following ingestion; skin irritation upon contact with seeds, rootstock, or cell sap. Highest concentration in rhizomes
Toxic principle
Pentacylic terpenoids (zeorin, missourin and missouriensin), Irisin, iridin, or irisine
Contact dermatitis
Yes
Toxicity summary
Low severity poison; parts: Roots; Sap/Juice; Seeds; contact dermatitis

Planted at Hunnicutt

Nobody’s planted this one yet.