Species Iris Group of North America

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Iris virginica

Botanical Name: Iris virginica (added by D. Kramb, 27-OCT-03)

Botanical Synonyms:



Beardless, Apogon, Laevigatae (D. Kramb, 31-AUG-04)

Common Names:

Southern blue flag (D. Kramb, 27-OCT-03)

Chromosome Count:

2n=70 or 2n=72 (D. Kramb, 31-AUG-04)

General Description:

Leaves are dark green to grayish green. Fans are spaced 8" or more with 3 to 12 leaves. Most are conspicuously rippled without a central rib. Basal foliage varies considerably in hieght from 8" to 36", width is 1" to 1.75". Stalks are upright, usually unbranched, sometimes with one branch, up to 4 buds per stalk. Stalks reach 12" to 32" in height. Flowers are relatively large, 3" to 4" in diameter, blooming later than I. versicolor and slightly later than I. virginica var. shrevei. Standards are almost the same length as the falls, 1" to 2.75" long, 1" to 1.25" wide. Standards are the same color or slightly darker than the falls. The falls are from 1.5" to 3" long and 1" to 1.5" wide with a striking bright yellow signal, surrounded by dense white veins. Stylearms are half the size of standards, of lighter color with darker central line. The crest is the same color as the standards. (D. Kramb, 31-AUG-04)

Seedpods are almost spherical with a warty surface, 1.5" to 2" long, and 0.75" to 1.25" in diameter. The pods are not durable and often are damaged before all seeds ripen. Seeds take 60 days to mature from time of fertilization. Each of the three carpels contain a zigzag layer of seeds. Seeds are rounded or D-shaped. The outer coat is very corky with a dull surface. In the wild seeds germinate in the fall. They germinate easily with plenty of humidity and heat, 80 deg F or over. Seedlings rarely bloom before the third year. (D. Kramb, 31-AUG-04)

Distinguishing Features:

Seeds are larger than that of I. virginica var. shrevei. Decorticated (husked) seeds are bigger and lighter brown that ssp. shrevei. In the wild seeds germinate in the fall. (D. Kramb, 31-AUG-04)

Preferred Habitat:

Likes wetter conditions than common bearded irises (D. Kramb, 27-OCT-03)

Grows in rich, moist, and acid soil. Performs best in shallow water. (D. Kramb, 31-AUG-04)


Not winter hardy in Montreal, Canada. Estimated Zone 6-10. (D. Kramb, 31-AUG-04)

Native Range:

Eastern North America, growing from Virginia to Florida, westward to Texas. (D. Kramb, 31-AUG-04)

Status in the Wild:

Probably common (D. Kramb, 27-OCT-03)

Commercial Availability:

Specialty, frequently available in SIGNA seed exchange (D. Kramb, 27-OCT-03)

Sources Cited:

Information added on 31-AUG-04 is taken from the SIGNA bulletin issue#60, Spring 1998, page 3118-19. Article written by Tony Huber from Laval, Canada. (D. Kramb, 31-AUG-04)

Additional Comments:


Where to buy it:

Arrowhead Alpines

Durio Nursery

Ensata Gardens

Iris City Gardens

SIGNA member!

Iris Haven

Joy Creek Nursery

Meadowbrook Nursery

Nicholls Gardens

Pine Ridge Gardens

Plant Delights Nursery

Siberian Iris Gardens

SIGNA member!

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