Also known as 'bachelor buttons', centaurea cyanus has piercing blue upright flowers that grow in mounds along with attractive silvery-grey leaves.  Enjoy their most beautiful bright blue coloured double blooms all summer long. Bees and butterflies will love them too. Happy in a sunny spot, cornflowers are very easy to grow from seed. They are ideal for borders, or for a cutting garden. They make great for cut flowers and can be easily dried and preserved, maintaining their bright blue shades even when dry. Height: Up to 65cm.