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Centaurea nigra
Also called Lesser Knapweed, Spanish Buttons, Black Knapweed, Black Starthistle, Hardheads
Common knapweed is a hardy upright perennial wildflower native to Europe, with purple thistle-like flower heads that attract pollinators. It spreads by rhizomes and self-seeding, so it is best grown in meadows or wild areas rather than borders.
Centaurea nigra is a species of flowering plant in the family Asteraceae, and is also known as lesser knapweed, common knapweed, black knapweed and bell weed.
It is native to central Europe, and has been introduced to temperate North America and Australasia, where it is usually regarded as a noxious weed due to its fast spread, hardiness and competitive potential.
Centaurea nigra boasts high nectar and pollen production relative to other British perennial meadow flowers. Nectar, pollen and seeds are highly important food resources to many species of invertebrates and birds. In its native range, C. nigra can therefore greatly improve biodiversity values and ecosystem services, such as pollination, when planted with a variety of other forbs, for example on field margins.
Centaurea behen · Dusty miller · Cornflower · Fiordaliso di Capraia · Maltese star-thistle · Perennial Cornflower · Yellow star-thistle · Spotted knapweed · Centaurea tchihatcheffii
Text excerpted from the Wikipedia article Centaurea nigra by its contributors, under CC BY-SA 4.0; the excerpts and the care summary drawn from them are shared under the same licence.
The care summary was written by AI (Claude, Anthropic) from the sources on this page, with general growing knowledge where they are silent. Check before relying on it.
Life form, climate and native range: World Checklist of Vascular Plants, Royal Botanic Gardens, Kew (CC BY 3.0), reformatted; see Plants of the World Online.
