Name: Common Knapweed
Scientific name: Centaurea nigra
Nature Stars: 60
About: This hairy, thistle-like plant likes grassland, road verge, sea cliffs and wasteground. It is hardy and grows well in good conditions. Flowers between June and September.
How to identify: The flower looks a bit like a more purple cornflower, with an almost shredded look to the fringed petals.
Where: Very common across all of the UK and Ireland
Fantastic fact: Due to its hardy and fast spreading nature, this plant is considered an invasive weed in North America.
Photograph credit: Philip Precey