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Similar but less problematic plants:
Iris versicolor Flower detail
Iris pseudacorus is often confused with:
Iris tridentata Form
Iris versicolor Flower detail
Native alternative(s) for Iris pseudacorus:
Asclepias incarnata Close up of flower
Iris tridentata Form
Iris virginica Iris virginica
Kosteletzkya pentacarpos Flower detail
Pontederia cordata Pontederia cordata
Plants that fill a similar niche:
Convallaria majalis leaves and flowers
Nandina domestica Growing Form
Wisteria floribunda Full bloom
Iris pseudacorus has some common insect problems:
Slugs and Snails Found on Flowers and Foliage
Iris pseudacorus has some other problems:
Weed Management

Yellow Flag Iris pseudacorus

Other Common Name(s):

Phonetic Spelling
EYE-ris su-dah-KOR-us
This plant has low severity poison characteristics.
See below
Description

Yellow flag iris perennial blub in the Iridaceae (iris) family native to Eurasia and Africa.  The genus name Iris is named after the Greek Goddess of rainbows and the common name, "flag", comes from an old English word (flagge) for reeds and refers to its natural preference to wetlands.

The showy yellow flowers appear in the spring and its bright green sword-shaped clumping foliage reaches up to 3 feet in height.   These plants grow aggressively and spread quickly in wet soils including water up to 10 inches deep or the wet muds along a pond.   Yellow flag iris spreads by rhizomes and seeds and can quickly overtake native plants in wet sites. Although it prefers full sun and boggy sites, it can adapt to somewhat drier sites in moist to wet gardens.

While it is a popular perennial planted at the edge of ponds and waterways, the North Carolina Invasive Plant Council lists yellow flag iris as invasive.  Invasive plants are especially threatening to wetland habitats due to their ease of spread through seeds and plantlets, and through their rapid growth.  See native plant alternatives in the left-hand column.

Insects, Diseases, and Other Plant Problems:  Listed as invasive by the NC Invasive Plant Council. It is also listed as invasive in Virginia and several other northeastern states as well as several northwestern states.

See this plant in the following landscapes:
Dry Rock Stream Garden Floricyle
Cultivars / Varieties:
Tags:
#showy flowers#yellow flowers#high maintenance#fast growing#aggressive#rhizomes#naturalizes#clumping#wet soils tolerant#HS302#problem for cats#problem for dogs#problem for horses#weed#boggy sites
 
Cultivars / Varieties:
Tags:
#showy flowers#yellow flowers#high maintenance#fast growing#aggressive#rhizomes#naturalizes#clumping#wet soils tolerant#HS302#problem for cats#problem for dogs#problem for horses#weed#boggy sites
  • Attributes:
    Genus:
    Iris
    Species:
    pseudacorus
    Family:
    Iridaceae
    Uses (Ethnobotany):
    The rhizome has been used in herbal medicine. The plant also has the ability to take up heavy metals out of water.
    Life Cycle:
    Perennial
    Country Or Region Of Origin:
    Europe, north Africa, western Asia
    Distribution:
    It has naturalized in much of the USA
  • Whole Plant Traits:
    Plant Type:
    Herbaceous Perennial
    Water Plant
    Weed
    Habit/Form:
    Clumping
    Growth Rate:
    Rapid
    Maintenance:
    High
  • Cultural Conditions:
    Light:
    Full sun (6 or more hours of direct sunlight a day)
    Soil pH:
    Acid (<6.0)
    Neutral (6.0-8.0)
    Soil Drainage:
    Frequent Standing Water
    Moist
    Occasional Flooding
    Occasionally Wet
    Available Space To Plant:
    12 inches-3 feet
    NC Region:
    Coastal
    Mountains
    Piedmont
    USDA Plant Hardiness Zone:
    5a, 5b, 6a, 6b, 7a, 7b, 9a, 9b
  • Fruit:
    Fruit Type:
    Capsule
    Fruit Description:
    The fruit is a dry 3-sided capsule 1.5–3 in long, containing numerous pale brown seeds.
  • Flowers:
    Flower Color:
    Gold/Yellow
    Flower Inflorescence:
    Panicle
    Flower Value To Gardener:
    Showy
    Flower Bloom Time:
    Spring
    Summer
    Flower Size:
    3-6 inches
    Flower Description:
    3-4 inch yellow iris-type flowers with several flowers per stem April to June
  • Leaves:
    Leaf Color:
    Green
    Leaf Type:
    Simple
    Leaf Arrangement:
    Whorled
    Leaf Shape:
    Linear
    Leaf Margin:
    Entire
    Hairs Present:
    No
    Leaf Length:
    > 6 inches
    Leaf Width:
    1-3 inches
    Leaf Description:
    Erect sword-shaped leaves are up to 35 inches long and 1.2 inches wide. Parallel venation and smooth margins
  • Stem:
    Stem Color:
    Green
    Stem Is Aromatic:
    No
    Stem Surface:
    Smooth (glabrous)
    Stem Description:
    The flowering stalk is stout and glabrous
  • Landscape:
    Resistance To Challenges:
    Wet Soil
    Problems:
    Problem for Cats
    Problem for Dogs
    Problem for Horses
    Weedy
  • Poisonous to Humans:
    Poison Severity:
    Low
    Poison Symptoms:
    Salivation, vomiting, drooling, lethargy, diarrhea. Highest concentration in rhizomes
    Poison Toxic Principle:
    Pentacylic terpenoids (zeorin, missourin and missouriensin)
    Causes Contact Dermatitis:
    No