Iris virginica var. shrevei

Species Native to Missouri
Common Name: southern blue flag 
Type: Herbaceous perennial
Family: Iridaceae
Native Range: Eastern United States
Zone: 5 to 9
Height: 1.50 to 2.00 feet
Spread: 1.50 to 2.00 feet
Bloom Time: June
Bloom Description: Violet-blue with yellow and white crested
Sun: Full sun
Water: Medium to wet
Maintenance: Low
Suggested Use: Water Plant, Rain Garden
Flower: Showy, Fragrant, Good Cut
Attracts: Butterflies
Tolerate: Deer, Clay Soil, Wet Soil

Culture

Best grown in wet, boggy, acidic to neutral, sandy soils in full sun. In the wild, the roots of this iris are often under water for protracted periods of time. These growing conditions are obviously rather difficult to duplicate in most home landscapes, making this iris somewhat of a challenge to grow well. It will, however, grow in average garden soils that are kept uniformly moist, but will usually grow smaller than in the wild. Spreads by rhizomes to form colonies in optimum growing conditions.

Noteworthy Characteristics

Iris virginica, commonly called southern blue flag, is native primarily to wetlands, marshes, lake sides, stream banks, and other moist, open areas in the eastern half of the United States and southern Canada. Two varietals are recognized: I. virginica var. virginica, which is found on the Atlantic coastal plain from Virginia to peninsular Florida and west to Texas, and I. virginica var. shrevei, which is found in the central United States and southern Canada from Arkansas north to the Great Lakes region and east to Quebec and the Appalachian Mountains. It typically grows to 2' tall (less frequently to 3') and features non-fragrant violet-blue flowers with falls that are crested with yellow and white. Flower color can vary considerably from very light blue to purple. Bright medium green, sword-shaped leaves often lie on the ground or in the water. Blooms in late spring.

Var. shrevei, often called Shreve's iris, is similar in appearance to the species but typically has branched inflorescences (versus unbranched) and longer, narrower seed capsules (2.75-4.25" long versus 1-2.25" long). This varietal also prefers a more neutral soil pH.

Genus named for the Greek goddess of the rainbow.

Specific epithet means of Virginia. The infraspecific epithet shrevei honors American botanist Forrest Shreve (1878-1950).

Problems

No serious insect or disease problems. Optimum growing conditions may be difficult to attain in the home landscape.

Uses

Water gardens, along streams or ponds or in low-lying areas that are subject to periodic flooding. May be grown in borders as long as soils are kept uniformly moist. Flowers are suitable for use in fresh cut arrangements. The rhizomes have traditionally been used by various Native American tribes to treat a number of ailments.