Centaurea montana - perennial cornflower (mountain bluet, bachelor’s button)
The blue-flowered perennial cornflower is at its best in a woodland garden where it may spread freely. If the site is not too rich, the perennial cornflower will spread moderately via rhizomes. Its habit is also better on these sites. These prerequisites are met in the arid, stony north end of Mustila’s Pähkinärinne (Walnut slope) where countless perennial cornflowers blossom at the height of summer.