Form: herbaceous — annual or biennial
Status: present in WA
An erect annual (occasionally biennial) herb to 1.5 metres high, commonly 30-60 centimetres, reproducing by seed. Native to southern Europe. Widespread throughout the south-west of WA, and the eastern Goldfields.
Stems: one to several stems arise from base, much branched and covered with stiff white hairs.
Leaves: alternate, bristly. Rosette leaves to 25 centimetres long, oval to oblong, stalked and with distinct lateral veins. Stem leaves are smaller and narrower, not stalked and almost clasping the stem.
Flowers: purple, rarely pink or white, crowded along one side of a curved spike. Five petals joined in a curved trumpet shape, two to three centimetres long. Five stamens, two of which are longer than the others and extend beyond the petals.
Fruit: a group of four nutlets surrounded by a stiffly bristled calyx.
Seeds: brown to grey, two to three millimetres long, three sided strongly wrinkled and pitted.
Online weed identification training
Login or set up a new account on DAFWAs online training site to access:
- a training course on how to identify Paterson's curse and report it.
- training material that you can use to teach community groups how to identify Paterson's curse.
Agricultural and economic impact
Paterson's curse is competitive in crops, invades pastures and can be toxic to livestock. Paterson’s curse is particularly toxic to horses.
Declared pest category
The Western Australian Organism List (WAOL) contains information on the area(s) in which this pest is declared and the control and keeping categories to which it has been assigned in Western Australia (WA). Use the following WAOL link to reach the declaration and declaration map for: Paterson's curse.
Requirements for land owners/occupiers and other persons
Requirements for land owners/occupiers and other persons if this pest is found can be sourced through the declared plant requirements link.
Search > detect > report
Detectability: easy to find. Paterson’s curse is one of the best known and most easily recognised declared plants. With its spring display of purple flowers, it’s not likely to be confused with any other weed. Its bristly stems and leaf-rosettes are also distinctive.
Who is likely to find it: potentially anyone in the South West Land Division could find Paterson’s curse including biosecurity groups, local government, and any landholder particularly horse owners.
When to find it: easiest to identify when in flower, mainly in spring, but it can flower at other times of year if conditions are favourable.
Where to find it: Paterson’s curse is most common in the Geraldton area and the Swan and Avon Valleys, but can be found down to the south coast and eastward to the Goldfields. It is often found in paddocks and on disturbed soils including roadsides.
Management calendar: a faded icon means occasionally
Further information on Paterson's curse can be found through the Paterson's curse: what you should know page.