Species Iris Group of North America

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Iris giganticaerulea

Botanical Name: Iris giganticaerulea (added by D. Kramb, 01-JAN-04)

Botanical Synonyms:



Louisiana Iris, Hexagonae, Apogon, Beardless Iris (D. Kramb, 01-JAN-04)

Common Names:

Giant blue flag (D. Kramb, 01-JAN-04)

Chromosome Count:

2n=44 (D. Kramb, 20-SEP-04)

General Description:

Flowers are 5" to 6" (13 to 15cm) across, predominantly blue to blue-purple and sometimes white. Flower form is typically flaring. (D. Kramb, 01-JAN-04)

Stalks grow from 28" to 71" tall. Flowers are pale to dark blue with a yellow signal ridge. (D. Kramb, 20-SEP-04)

Distinguishing Features:

This is the largest species in the Hexagonae series. Rhizomes are very large, from 5" to 12" and 0.75" to 1.5" thick. Can grow to 66" tall. (D. Kramb, 01-JAN-04)

Preferred Habitat:

Grows in full sun or partial sun, in open swamps. Thrives under flooded conditions and tolerates brackish water. (D. Kramb, 01-JAN-04)


Estimated Zones 7-11. Can probably survive to Zone 5 or 6 with winter protection. (D. Kramb, 01-JAN-04)

Native Range:

USA (Louisiana and southeast Texas, from coastal areas to 100 miles inland) (D. Kramb, 01-JAN-04)

Status in the Wild:


Commercial Availability:

Specialty. Often available at water garden centers. (D. Kramb, 01-JAN-04)

Sources Cited:

Most information added on 01-JAN-04 comes from the book (D. Kramb, 01-JAN-04)

Info entered on 20-SEP-04 comes from the SIGNA Checklist of Iris Species. (D. Kramb, 20-SEP-04)

Additional Comments:

This species is extremely variable in the wild. (D. Kramb, 01-JAN-04)

Where to buy it:

Durio Nursery

Pine Ridge Gardens

Zydeco Louisiana Iris Garden

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