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perennial

Japanese Water Iris

Iris ensata

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Japanese Water Iris (Iris ensata) at Kennedy's Country Gardens

Japanese Water Iris flowers

Japanese Water Iris flowers

(Photo courtesy of NetPS Plant Finder)

Plant Height:  24 inches

Flower Height:  3 feet

Spacing:  18 inches

Sunlight:  full sun 

Hardiness Zone:  4b

Group/Class:  Japanese Water

Description:

This iris has very high water needs and doesn't like to dry out

Ornamental Features

Japanese Water Iris features showy white flag-like flowers with purple overtones and yellow throats at the ends of the stems from mid spring to mid summer. The flowers are excellent for cutting. Its attractive sword-like leaves remain bluish-green in color throughout the season.

Landscape Attributes

Japanese Water Iris is an herbaceous perennial with tall flower stalks held atop a low mound of foliage. Its medium texture blends into the garden, but can always be balanced by a couple of finer or coarser plants for an effective composition.

This plant will require occasional maintenance and upkeep, and should be cut back in late fall in preparation for winter. Deer don't particularly care for this plant and will usually leave it alone in favor of tastier treats. It has no significant negative characteristics.

Japanese Water Iris is recommended for the following landscape applications;

  • Mass Planting
  • Border Edging
  • General Garden Use
  • Container Planting
  • Bog Gardens

Planting & Growing

Japanese Water Iris will grow to be about 24 inches tall at maturity extending to 3 feet tall with the flowers, with a spread of 24 inches. When grown in masses or used as a bedding plant, individual plants should be spaced approximately 18 inches apart. Its foliage tends to remain dense right to the ground, not requiring facer plants in front. It grows at a medium rate, and under ideal conditions can be expected to live for approximately 10 years. As an herbaceous perennial, this plant will usually die back to the crown each winter, and will regrow from the base each spring. Be careful not to disturb the crown in late winter when it may not be readily seen!

This plant should only be grown in full sunlight. It is quite adaptable, prefering to grow in average to wet conditions, and will even tolerate some standing water. It is not particular as to soil type or pH. It is somewhat tolerant of urban pollution. This species is not originally from North America. It can be propagated by division.

Japanese Water Iris is a fine choice for the garden, but it is also a good selection for planting in outdoor pots and containers. With its upright habit of growth, it is best suited for use as a 'thriller' in the 'spiller-thriller-filler' container combination; plant it near the center of the pot, surrounded by smaller plants and those that spill over the edges. It is even sizeable enough that it can be grown alone in a suitable container. Note that when growing plants in outdoor containers and baskets, they may require more frequent waterings than they would in the yard or garden.

 
 
Hardiness Zone Plant Height Minimum Sunlight
Characteristics
Massing  Edging  Garden  Container  Bog 
Applications
Flowers  Foliage Color  Plant Form 
Ornamental Features