Culture
Grow in average, medium moisture, well-drained soils in full sun. Tolerates some part afternoon shade. Best performance occurs in light soils with excellent drainage. Plant bulbs 3-5” deep and 3-5” apart in fall. Provide consistent moisture during the growing season. Leaves should be left in place after spring bloom. Foliage will turn yellow as the plants enter dormancy, at which point the yellow leaves may be removed. No supplemental watering is needed when plants are dormant. Bulbs tend to separate into offsets or bulblets after bloom (particularly when planted shallowly), with each new bulblet requiring several years to mature. Dutch iris bulbs tend to be short-lived. In order to insure consistent flowering from year to year, bulbs may be dug and divided after bloom or supplemental bulbs may be planted each fall. Another option is to grow this iris as an annual and plant new bulbs each fall.
Noteworthy Characteristics
Dutch iris is a bulbous iris whose hybrids were developed by Dutch growers. It is a form of Spanish iris that is included in the Iris xiphium group. Dutch hybrids are slender plants that typically grows to 15-24” (sometimes to 30”) tall, and feature a May-June bloom (St. Louis) of flowers (3-4” wide) with slim, upright standards and downward falls, primarily in colors ranging from blue to yellow to white. Flowers often have a yellow blotch on the falls. Narrow linear green leaves. Dutch hybrids are excellent cut flowers that are commonly sold by florists. They are often grown as annuals.
Genus named for the Greek goddess of the rainbow.
Problems
Leaf spot, root rot and mosaic virus may appear. Iris borers.
Uses
Best grouped or massed in sunny areas of the landscape. Also may be grown in containers. Excellent cut flower. May be forced in greenhouses throughout the year.