Amaranthus retroflexus L.

Redroot Amaranth

Sp. Pl. 991 (1753) APNI

Taxonomic status:Accepted

Occurrence status:Present

Establishment means:Naturalised

Erect annual to c. 1.2 m high. Stems angled or grooved, glandular pubescent, sometimes reddish. Roots reddish. Leaves long-petiolate, ovate to rhombic, lamina 2–14 cm long, 1–8 cm wide; margin often crenulate and/or undulate; apex sometimes shortly mucronate. Spikes dense, crowded toward the ends of branches and in upper axils, to c. 10 cm long, 1–2 cm diam., greenish or reddish. Flowers unisexual; longest bracts and bracteoles lanceolate, 3–5 mm long, spinescent; tepals 5, oblong, 1.5–3 mm long, obtuse, truncate or emarginate, often shortly mucronate; stamens 5. Utricle circumsciss, subequal to perianth; seed discoid, brown, shiny, 1–1.5 mm diam. Flowers Feb.–May.

*CVU, *GipP, *Gold, *HSF, *MuF, *MuM, *NIS, *VRiv, *VVP, *WaP, *Wim. Also naturalised WA, NT, SA, Qld, NSW, ACT. Native to North America. Occasional weed of paddocks, gardens and disturbed open ground, mostly near cities (e.g. Horsham, Ballarat, Melbourne, Shepparton areas).

Source: Walsh, N.G. (1996). Amaranthaceae. In: Walsh, N.G.; Entwisle, T.J. (eds), Flora of Victoria Vol. 3, Dicotyledons Winteraceae to Myrtaceae. Inkata Press, Melbourne.
Updated by: Val Stajsic, 2018-04-18
Hero image
Distribution map
life Life
kingdom Plantae
phylum Tracheophyta
superorder Caryophyllanae
family Amaranthaceae
genus Amaranthus
Higher taxa


Source: AVH (2014). Australia's Virtual Herbarium, Council of Heads of Australasian Herbaria, <>. Find Amaranthus retroflexus in AVH ; Victorian Biodiversity Atlas, © The State of Victoria, Department of Environment and Primary Industries (published Dec. 2014) Find Amaranthus retroflexus in Victorian Biodiversity Atlas
  Bioregion Occurrence status Establishment means
Murray Mallee present naturalised
Wimmera present introduced
Victorian Volcanic Plain present naturalised
Victorian Riverina present naturalised
Murray Fans present introduced
Gippsland Plain present naturalised
Warrnambool Plain present introduced
Goldfields present naturalised
Central Victorian Uplands present naturalised
Northern Inland Slopes present naturalised
Highlands-Southern Fall present naturalised

State distribution

Distribution map
Western Australia
Northern Territory
South Australia
New South Wales
Australian Capital Territory