T.E.R:R.A.I.N - Taranaki Educational Resource: Research, Analysis and Information Network


Cirsium palustre (Marsh Thistle)

Kingdom: Plantae
(Unranked): Angiosperms
(Unranked): Eudicots
(Unranked): Asterids
Order: Asterales
Family: Asteraceae
Tribe: Cynareae
Genus: Cirsium
Species: C. palustre
Binomial name: Cirsium palustre
Common names: Marsh thistle, Swamp thistle

Cirsium palustreis is an herbaceous biennial (or often perennial) species of the genus Cirsium. It is a tall thistle which reaches up to 2 metres in height. The strong stems have few branches and are covered in small spines.
In its first year the plant grows as a dense rosette, at first with narrow, entire leaves with spiny, dark purple edges; later, larger leaves are lobed.
In the subsequent years the plant grows a tall, straight stem, the tip of which branches repeatedly, bearing a candelabra of dark purple flowers, 10–20 millimetres with purple-tipped bracts. In the northern hemisphere these are produced from June to September. The flowers are occasionally white, in which case the purple edges to the leaves are absent. It is native to Europe where it is particularly common on damp ground such as marshes, wet fields and beside streams. In New Zealand it is an introduced species that has become invasive in higher rainfall areas.

Photographed West Coast, New Zealand.












Cirsium palustreis can grow over 2 m tall.