Onopordum is a genus of flowering plants in family Asteraceae, comprising about 40 species. It is native to Europe (Mediterranean region), northern Africa, the Canary Islands, the Caucasus, and southwest and central Asia. Onopordum has a common name called Scotch Thistle.
Onopordum is a biennial plant, with branched, spinose winged stems. It can grow to a height of 0.5-3 m, with silvery foliage. The leaves are dentate with deeply cut leaflets and strongly spiny. The flowers do not appear until the second year and the plants die off after seed maturation. The seed head mature in mid-summer, releasing the seeds.
Onopordum species are also food plant to larvae of some Lepidoptera species including Coleophora onopordiella which feeds exclusively on O. acanthium.
Plant Onopordum in full sun, fertile, well-drained and neutral to alkaline soil. The plants propagate only by seed. Pests are slugs and snails.