- Flower nameAcorus calamus
- Scientific nameAcorus calamus
- Alias菖蒲, 葉菖蒲, ハショウブ, 匂い菖蒲, アヤメグサ, Ayamegusa
- Place of originEurasia to North America
- Place of floweringCut flowers, flower arrangement, River, pond, Rice paddies
- Flowering seasonMay, June, July
What is Acorus calamus
Acorus calamus, calamus, Sweet Flag, shoubu, or Ayamegusa (scientific name: Acorus calamus) is a water-extracting perennial herb of the genus Iris of the Showbush family, native to Eurasia and North America. It is found in ponds and swamps throughout Japan, and its rhizomes grow in the mud. Unlike plants of the taro family, it does not produce potatoes. The leaves are sword-shaped, green, and alternate in double rows. The inflorescence is produced between the leaves, but the bracts resemble the leaves, making it look as if the inflorescence is produced from the center of the leaf. The flowers are rod-shaped and plain, but the entire plant contains an essential oil component with a fragrance. This fragrance has long been believed to exorcise evil spirits and has been used in annual festivals to pray for good health. Even today, there is a custom of making a "shobuyu" (hot water with iris rhizomes and leaves) or hanging them from the eaves of houses to ward off evil spirits during the Boys' Festival on May 5. Calamus is a completely different plant, belonging to a different family and genus than the iris, which is a member of the iris family and has beautiful flowers.
Common name: Acorus calamus, scientific name: Acorus calamus, aka : calamus, sweet flag, place of origin: Eurasia to North America, habitat distribution: ponds and swamps throughout Japan, Height: 50-120 cm, Leaf length: 50-120 cm, Leaf width: 1-2.5 cm, Leaf shape: sword-shaped, Leaf color: green, Inflorescence: alternate in 2 rows, Inflorescence length: 4-8 cm, Inflorescence diameter: 0.6-1 cm, Inflorescence shape: cylindrical, Inflorescence form: pendulous, Bract length: 20-40 cm bract width: 0.5-0.8 cm, petiole color: light yellowish green, petiole diameter: 0.5 cm, number of petioles: 6, flowering season: May-July, fruit color: red, fruit type: liquid fruit, fruit shape: oblong, uses: cut flower, park, paddy field greening, medicinal herb, Chinese medicine.