Iris pseudacorus L.

Yellow Flag Iris

Sp. Pl. 38 (1753) APNI

Taxonomic status:Accepted

Occurrence status:Present

Establishment means:Naturalised

Leaves 40–100 cm long, 1–3 cm wide. Inflorescences usually exceeding leaves, with scape up to 160 cm long, 1- or 2-branched, with 2–4 condensed 2–6-flowered clusters. Primary bracts 6–13 cm long. Flowers yellow, usually with some brown or violet veining and a darker yellow zone (absent in some forms). Perianth tube 1–1.5 cm long; sepals broadly ovoid to broadly obovoid or rhombic, 4.5–6 cm long, recurved, glabrous; petals distinctly narrower than sepals, 2–4 cm long, ascending to recurved, glabrous. Seeds dull brown. Flowers Oct.–Nov.

*EGL, *GipP, *HSF, *VRiv, *VVP. Also naturalised SA, NSW, ACT. Native to northern Africa Europe, temperate Asia. A vigorous weed species which occasionally escapes from gardens and colonizes ditches and banks of watercourses (e.g. Yarra River at Yarra Glen).

Source: Conn, B.J. (1994). Iridaceae. In: Walsh, N.G.; Entwisle, T.J. (eds), Flora of Victoria Vol. 2, Ferns and Allied Plants, Conifers and Monocotyledons. Inkata Press, Melbourne.
Updated by: Val Stajsic, 2019-07-23
Distribution map
life Life
kingdom Plantae
phylum Tracheophyta
superorder Lilianae
order Asparagales
family Iridaceae
genus Iris
Higher taxa


Source: AVH (2014). Australia's Virtual Herbarium, Council of Heads of Australasian Herbaria, <>. Find Iris pseudacorus in AVH ; Victorian Biodiversity Atlas, © The State of Victoria, Department of Environment and Primary Industries (published Dec. 2014) Find Iris pseudacorus in Victorian Biodiversity Atlas
  Bioregion Occurrence status Establishment means
Victorian Volcanic Plain present naturalised
Victorian Riverina present introduced
Gippsland Plain present naturalised
East Gippsland Lowlands present naturalised
Highlands-Southern Fall present naturalised

State distribution

Distribution map
South Australia
New South Wales