Quick Guide: summer, hardy, sun, height: 90cm/3ft, width: 30cm/12in
Centaurea cyanus, the cornflower, is a sturdy border plant with blooms of pure blue, pink or white that make excellent cut flowers. Its cousin sweet sultan, C. moschata, reaches only 60cm/24in and bears fragrant flowers of white, yellow, pink or deep purple.
PROPAGATION Sow seeds in the open where they are to grow in spring, or in the autumn with the protection of cloches over winter for early flowering the following year. Thin the seedlings to 23cm/9in apart.
GROWING Any fertile, well-drained soil is suitable. Choose a site protected from winds and give taller varieties the support of twiggy sticks. Dead-head regularly to encourage prolonged flowering.
VARIETIES C. cyanus: 'Dwarf Blue'; `Polka Dot' includes a variety of COI-ours; `Dwarf Rose Gem' is a compact pink-flowered variety good for growing in pots. C. moschata: no named varieties, but C. m. imperialis is a reliable form with large flowers.
POSSIBLE PROBLEMS Petal blight; rust.
