Centaurea montana ( perennial cornflower, mountain cornflower, bachelor's button, montane knapweed or mountain bluet) is a species of Centaurea endemic to Europe. To grow Centaurea montana from seed, sow 8-10 seeds per pot in late Summer to early Winter indoors. Cover with 1/2″ soil & mist to moisten. Needs darkness to germinate. Cover with clear plastic, maintain 60-70F for germination 17-21 days.