Milk Thistle is native to the Mediterranean, but due to its widespread availability across the globe, it is also recognised as Saint Mary’s Thistle, Blessed Milk Thistle, Holy Thistle and Our Lady’s Thistle.
It is a member of the Asteraceae family (a relative to sunflowers and daisies) and is recognised as an annual or biennial herb. With its dense-prickly flower head and reddish-purple tubular flowers, this plant is considered a weed and invasive in some parts of the world because of its ability to spread quickly.
Its common name, Milk Thistle, derives from its characteristic milky-white veins on the leaves, which when broken open, produce a milky sap. According to legend, it was believed to carry the milk of the Virgin Mary, which may help explain its name variations.