Centaurea dealbata

Family: Compositae

Common names: HARDHEADS, KNAPWEED, STAR THISTLE

Native to: Caucasus

Plant

Type: perennial

Forms: erect, rosette, tufted

Max height: 3.3 feet

Max width: 2 feet

Flower

magenta/purple, pink

Leaf

green

Horticulture

Attracts wildlife: adult butterfly, specific butterfly species

Exposure: sun

Propagates by: seed

flowers in summer

Soil type: wide range

USDA Zones: zone 3 -40 f, zone 4 -30 f, zone 5 to -20 f, zone 6 to -10 f, zone 7 to 0 f, zone 8 to +10 f, zone 9 to +20 f

Temp. range: -40 to +30 °F

Water: moderate

  • Centaurea dealbata
  • Centaurea dealbata 2

Centaurea, also called HARDHEADS, KNAPWEED, or STAR THISTLE, is a member of the Aster family, Compositae. There are 924 species in this genus of which six or more are cultivated. Of those Centaurea dealbata, macrocephala, and montana are cultivated perennials. They grow 3-3 ½ feet tall in Zones 3-9, prefer moderate watering, and flower in summer.

Centaurea dealbata is a cultivated perennial can be grown from seed, is grown in full sun, and can be grown in containers.

As a member of the Compositae family it will attract a long list of butterflies to feed. In particular, the following butterflies feed on Centaurea blossoms:
Hylephila phyleus, Fiery Skipper
Junonia coenia, Common Buckeye
Pyrgus communis, Common Checkered-Skipper

Hylephila phyleus 3
Pyrgus communis