Centaurea nigra has generally unlobed leaves and bracts that are mostly brown, in contrast to greater knapweed, centaurea scabiosa, for which the leaves are deeply lobed, and the bracts are mostly green; brown only in a horseshoe-shaped arch along the upper edge.
Common name:
Common knapweed
Family:
Scientific name:
Centaurea nigra
Main flower color:
Range:
All across the UK
Height:
Up to 60 cm
Habitat:
Grassland, meadows, roadsides, disturbed ground
Flowers:
Flowerheads are usually solitary, up to 4 cm in diameter; they have a cluster of pink disc florets, some spreading when mature, above an egg-shaped involucre ringed with triangular bracts, mostly coloured brown though pale green at the base, with branched bristles along their margins. A few leaves grow just below the flowerhead
Leaves:
Narrowly lanceolate, with wavy edges and rough-hairy surfaces; those near the base may be shallowly lobed
Season:
June to September
Rarity:
★★★★★
