help to identify a thistle please. (I think?)

A few years ago I bought a little plant from a small garden centre. Due to moving home soon afterwards it stayed in its little pot for quite some time. I can't recall if it had an identifying tag/label. Anyway I never got round to planting it until late Spring 2010 & it was still small, not much growth, probably contained by the pot size.
By late summer 2010 it had happily established itself & was shooting away in a semi-shady position in my my back garden.
I think it's a thistle & have tried to identify it online with little success. Have only found one photo but without any description. I don't think it's the toxic Centaurea solstitialis yellow star thistle which seems to have caused lots of invasive problems as it doesn't have the star shaped thorny bits. If anyone can let me know just in case it is toxic or could be harmful. It's very distinctive & quite pretty in its own way. Would be a shame to have to dispose of it but safety first.
Thanks!

 

Could it be Centaurea macrocephala ? - which is an acceptable garden plant.


Photo: www.jennyflowers

 

Hi Peter,
Yes it is, have just searched Centaurea macrocephala & now having access to its correct name has confirmed your answer.
Thank you so much! I'm very fond of this plant & because it's seems so happy & at home in my garden hence giving me pleasure in return I would have been just a bit upset to have had to dispose of it.
It's also good to now know that it's a member of the Cornflowers - I'd never have quessed that.
Thank you again, much appreciated.
Palomita.

 

Glad to be able to help Palomita.