*Acorus calamus Linnaeus. Common name: European Calamus, Sweetflag. Phenology: May-Jun. Habitat: Marshes, wet meadows, other wet areas. Distribution: Native of Eurasia, now widespread in e. North America.
Origin/Endemic status: Eurasia
Taxonomy Comments: Following the taxonomy of Sokoloff et al. (2024), A. calamus consists of sterile triploids in Europe, w. Asia, and (presumably introduced) e. North America; diploid and tetraploid populations (in Asia) previously interpreted as part of A. calamus represent different species.
Other Comments: The aromatic rhizome and leaves have been used medicinally and candied as a confection.
Synonymy ⓘ: = AqW, Ar, Can, ETx1, FNA22, Il, K4, Mi, Mo1, NcTx, NE, NS, NY, Ok, Pa, POWO, Tx, Va, Spaulding et al (2019); < Acorus americanus (Raf.) Raf. — W; < Acorus calamus L. — C, F, G, GrPl, GW1, NeUS, RAB, S, S13, Tat. Basionym: Acorus calamus L. 1753
Links to other floras: = Acorus calamus - FNA22
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Wetland Indicator Status:
- Atlantic and Gulf Coastal Plain: OBL
- Eastern Mountains and Piedmont: OBL
- Great Plains: OBL
- Midwest: OBL
- Northcentral & Northeast: OBL
Heliophily ⓘ: 9
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© Gary P. Fleming | Original Image ⭷
© Bruce A. Sorrie | Original Image ⭷
© Bruce A. Sorrie | Original Image ⭷
© Erik Danielson source | Original Image ⭷
© Erik Danielson source | Original Image ⭷Feedback
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Horticultural Information
Intro: Stemless perennial found in marshes, wet meadows and other wet areas. Native of Eurasia, but now widespread in e. North America
Stems: Flowering stalk and leaves arise from a thick underground rhizome.
Leaves: Leaves 2-ranked and crowded basally, where they attach directly to the rhizome; linear and strap-like, to 70 in. long, with a prominent pink or red central vein and "crinkled" margins.
Inforescence:
Flowers: Flowers crowded in a stiff, linear-cylindric spike (2-4 in. long) that is attached at an angle near the middle of a long, leaf-like stem; greenish-yellow (later brownish), tiny.
Fruits:
Comments: Crushed leaves and rhizomes have a distinctive sweet smell; traditional uses of the rhizome range from medicinal to candy-making.
Height: 1-3 1/2 ft.
plant sale text:
bloom table text:
description: Stemless perennial found in marshes, wet meadows and other wet areas. Native of Eurasia, but now widespread in e. North America
stems: Flowering stalk and leaves arise from a thick underground rhizome.
leaves: Leaves 2-ranked and crowded basally, where they attach directly to the rhizome; linear and strap-like, to 70 in. long, with a prominent pink or red central vein and "crinkled" margins.
inflorescence:
flowers: Flowers crowded in a stiff, linear-cylindric spike (2-4 in. long) that is attached at an angle near the middle of a long, leaf-like stem; greenish-yellow (later brownish), tiny.
fruits:
comments: Crushed leaves and rhizomes have a distinctive sweet smell; traditional uses of the rhizome range from medicinal to candy-making.
cultural notes:
germination code:
native range: Europe & Asia
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