Height 60-90cm (2-3ft)
Planting distance 45-60cm (18-24in)
Flowers late summer to early autumn
An abundance of delicate, richly coloured-like , borne among pretty light green leaves makes these half-hardy annuals excellent for late summer colour in borders and containers. The flowers come in pinks, reds and white with yellow centres, or
Crepis hawksbeard shades of orange, vermilion and yellow. Growing on 60-90cm (2-3ft) high stems, they are also ideal for cutting.
Cosmos bipinnatus is the tallest species, reaching 90cm (3ft) high. It has white, crimson, rose or pink flowers with yellow central discs, and finely cut mid green leaves. Popular varieties include ‘Candy Stripe’ (white flowers with crimson stripes), ‘Gloria’ (rose-pink, central dark bands; up to 15cm/6in across); ‘Psyche’ (semi-double and single pink, red or white blooms with frilled petals), ‘Purity’ (white flowers) and ‘Sensation’ (white, pink, carmine and crimson flowers).
Cosmos sulphureus reaches just 60cm (2ft) high, and has yellow flowers accompanied by coarsely cut dark green leaves. Popular varieties include ‘Bright Lights’ (small double yellow, orange or scarlet flowers), ‘Diablo’ (orange- red flowers), ‘Lemon Twist’ (acid- yellow flowers) ‘Sunny Gold’ (semi-double, golden-yellow flowers) and ‘Sunny Red’ (double vermilion flowers).
Sow the seeds under glass in late winter or early spring and keep at a temperature of 16°C (61°F). Harden off in a cold frame before planting out in late spring.
Cosmeas prefer a poor, light soil in a hot dry corner. Stake the plants and dead-head regularly.
Pests and diseases
Aphids sometimes infest young plants.