Centaurea nigra

black knapweed or common knapweed

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9cm pot £5.99 £2.99
in stock (shipped within 3-5 working days)
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Buy Centaurea nigra black knapweed or common knapweed: Single purple thistle-like flowers with black fringe

  • Position: full sun or partial shade
  • Soil: moist but well-drained soil
  • Rate of growth: average
  • Flowering period: June to September
  • Hardiness: fully hardy

    Native grassland perennial found in meadows, scrub land and on woodland edges. This tough wildflower can be variable, but normally it has a whorl of brown/black bracts topped with a light purple/pink inflorescence, which sometimes can be white. Definitely a plant for your wildlife garden, or any garden that wants to attract the birds and bees. Once the flowerhead fades, the seedheads are loved by the birds but also this does mean that it can freely self seed.

  • Garden care: Wild flowers prefer poor soils, so do not apply fertiliser. Deadhead regularly to prolong flowering. In autumn, cut the faded flowerheads down to the ground and compost the dead stems.

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Eventual height & spread

Eventual height and spread
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Love my plants


I love all my plants from crocus.my first port of call when looking for plants. Always have what I'm looking for. They arrive in good condition and are looking good.

Sam gardener extraordinaire



Adds a Scottish feel to the garden.


Vivid colours.




Good plants, great for butterflies and bees.


Used in a wildlife and wild flower garden. Good plant for natural dyeing. Hardy and grows into strong plants.


Stratford upon Avon




Arguably the best bee/butterfly plant, bringing them in droves. Great for the border as well as meadow due to its unique and attractive flowers. Very tough and will grow just about anywhere. Can spread quite rapidly via seed...But not invasive.




A lovely native meadow plant


I have used this in public parks for meadow-like areas. Also on wild roadside verges. Delicious colour, insect attractor and one of my favourites.





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