South Dakota Native Plant Research
Acoraceae: Acorus americanus

Acoraceae: Acorus americanus


Download Seed: Sweet flag produces few seeds (54 KB)

Download Seedling: Seedling picture (116 KB)

Download Leaves (207 KB)

Download Rhizome (394 KB)

Download spathe and spadex (137 KB)

Family Name


Common Name

Sweet flag

Native American Name

Dakota: sinkpe-ta-wote; Lakota: sunka ce


Acorus americanus is a grass-like perennial herb, which grows 90-150 cm in height. The plant is strongly rhizomatous. The leaves are entire, sword shaped and erect. Sweet flag has a spadix that is 4-9 cm long with light brown greenish-brown perfect flowers that are enclosed by a leaf-like spathe. The perianth has 6 short segments, there are 6 stamens, and the pistil contains 2-3 locules. The fruit is a small capsule containing 2-3 seeds. Flowering occurs from May to July. This species is commonly found in swamps and marshes throughout South Dakota.

Additional Notes

The rhizomes are quite fragrant and are used both as medicines and food by several of the Northern Great Plains tribal peoples.

The Dakota name ""sinkpe-ta-wote"", means muskrat food.

Horticulture Notes

Seed Collection: Late summer, before seeds are shed.
Germination: Stratification over winter in moist soil.
Vegetative Propagation: By division of the rhizomes
Soils: Wet fertile soil
Light: Full sun
Water: Thrives in wet areas
Notes: The roots grow in a broad array just below the surface of the soil

Acoraceae: Acorus americanus