Centaurea cyanus. Centaurea are also known as Bachelor's Buttons. These familiar, charming, brightly-coloured pompoms on fuzzy grey stems, are well loved by humans and attractive to beneficial hover-flies. Blue Boy is at home in borders, with herbs, or in the kitchen garden. Direct sow Blue Boy cornflower seeds at repeated intervals in April to June to extend bloom. Centaurea can also be planted in October on the Coast. Blue Boy has the traditional vivid blue blossoms, tall growing for masses of cut flowers. Centaurea flowers also dry particularly well. Tear fresh flower petals for use in salads, teas, or fancy drinks. Plant height 90cm (36"). It is drought tolerant once established, so good for xeriscaping.