Japanese Iris

Japanese iris has the largest bloom of any iris and thrives in wet soil.


Plant type: Herbaceous perennial
Botanical name: Iris ensata
Hardiness: USDA Zones 4 to 9

Has the largest blooms of all the irises, up to 12 inches across. Valued for its ability to grow in wet conditions. The Japanese iris flower has upright petals, called standards, in addition to hanging petals, called falls. However, the standards are shorter and more flattened, giving the flower a relatively flattened appearance in comparison to other iris flowers, such as the more upright bearded iris. Flowers are white, rose, orange, yellow, purple and blue. Single- (has three falls), double- (has six falls) and peony-style (has nine or more falls) flowering types available. Blooms in summer. Foliage is green and grasslike and dies back after it has finished blooming. Plant size is 24 to 40 inches tall and 36 inches wide.

How to use it: Plant in mass for full effect. Use in the front to back of a mixed perennial border, in a bog garden or near a water feature.

Culture: Prefers a rich, acidic, moist to wet soil. If summers are dry, provide supplemental water to encourage blooming. Plant in full sun to light shade. Benefits by fertilization. Primarily propagated through division. Dig and divide only when plants show less vigorous flowering. Can be divided in spring (ideal) or fall. May have problems with iris borer, slugs or snails.

Deep Purple

Irises are grown from rhizomes. This purple variety has a velvety look and stands tall in the garden.

©2008, Dorling Kindersley Limited

Velvety Iris

The 'George' variety iris produces rich purple flowers that are vigorous but shorter than other varieties.

©2008, Dorling Kindersley Limited

Iris Sibirica 'Butter and Sugar'

Easy and trouble-free, the Siberian Iris ‘Butter and Sugar’ forms clumps of grassy foliage with a late spring display of butterfly-like flowers. These bicolored blossoms are large with creamy white standards and butter-yellow falls.

©2011, Dorling Kindersley Limited

Siberian Iris Blooms Large in Variety of Colors

Siberian iris is an herbaceous perennial plant with leaves that are glaucous green, narrow and fairly rigid, and blade shaped. The flowers are typical of an iris, borne in late spring or early summer. Come in variety of colors.

©2009, Dorling Kindersley Limited

Iris sibirica 'Illini Charm'

This striking purple iris is native to central Europe and Russia and often known by the more common name Siberian iris.

An Operatic Iris

The spring-flowering Iris germanica 'Beverly Sills' featuring coral-pink blooms takes its name from the operatic soprano.

Iris Katharine Hodgkin Springtime Flowering Bulb

Iris Katharine Hodgkin, a charming dwarf iris, really stands out from the crowd with its unusual pale blue and yellow coloring. The leaves are sword shaped and sometimes variegated, and the flowers have six sepals.

©2011, Dorling Kindersley Limited

Special notes: The name iris is derived from Greek mythology where Iris was the goddess of the rainbow, therefore aptly named for its variety of flower colors. Beardless iris. Japanese iris has rhizomes which are thick, fleshy stems that grow underground. Ideal for wet sites.

Selected Cultivars

  • 'Silverband'. Also known as 'Variegata'. Has white variegated foliage that is striking on its own. The violet-purple flowers bring this selection over the top. Used in the garden more for its foliage than flowers. Reaches three feet tall.


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