About

Cosmos bipinnatus 'Sea Shells' is a half-hardy annual that reaches heights of up to 1 meter. It features delicate, finely-divided foliage and produces unique flowers with fluted petals in various hues, including white, pink, and carmine red, all centered around a prominent yellow eye.

About the genus

Cosmos comprises both annual and perennial species characterized by either simple or pinnately divided foliage. These plants produce sizable, long-stemmed flowers resembling daisies during the summer months.

Growing conditions

Sunlight
Full sun
Soil type
Chalk, Clay, Loam, Sand
Soil pH
Acid, Alkaline, Neutral
Soil moisture
Moist but well-drained
Aspect
West-facing, South-facing, East-facing
Exposure
Sheltered
UK hardiness
H3

Plant details

Plant type
Annual Biennial
Habit
Clump forming
Foliage
Deciduous
Height
0.5-1 metres
Spread
0.5-1 metres
Time to full height
1 year
Suggested uses
Patio and container plants, Cottage and informal garden, Wildlife gardens

Care notes

Cultivation
Grow in moist, but well-drained soil in full sun. Suited to annual or cut-flower borders or as a summer infill
Pruning
Deadhead to prolong the flowering season
Propagation
See sowing seeds indoors
Pest resistance
May be susceptible to aphids and slugs
Disease resistance
May be susceptible to grey moulds