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


Best grown in wet, boggy, acidic, 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 a wetland species of iris which is native primarily to coastal plains from Virginia to Louisiana. 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 is native to inland swamps, marshes and flood plains in central North America (Ohio and Mississippi River basins and throughout the Great Lakes) including somewhat broad distribution in northern and central Missouri. Var. shrevei is similar in appearance to the species, but prefers a more neutral soil and is reportedly easier to grow in Missouri home landscapes.

Genus named for the Greek goddess of the rainbow.

Specific epithet means of Virginia.


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


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.