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A picture of a Cosmos 'Sea Shells Mix'

Cosmos 'Sea Shells Mix'

Cosmos bipinnatus 'Sea Shells Mix'

Also known as

Cosmos 'Seashells Mixed', Cosmea 'Sea Shells'

Photo by thejsheppard (All rights reserved)

Full Sun
Easy care
Light watering


RHS hardiness


Minimum temperature

Expected size








6 months to reach maturity


  • spring
  • summer
  • autumn
  • winter

This plant has no fragrance

Cosmos 'Sea Shells Mix' Overview

Cosmos 'Sea Shells' is a half-hardy, upright, bushy annual. Its bright green leaves are finely-divided, and from summer to early autumn, short, upright stems bear daisy-like flowers in white, pink, red shades around a central eye. These vibrant fluted petals curve around to create unusual tube shapes. Suited to a sunny border or patio container, Cosmos bipinnatus 'Sea Shells Mix' attracts a wide variety of pollinating insects and it is on the RHS 'Plants for Pollinators' list. As well as being great for wildlife, it is an easy-to-grow, versatile annual that makes a good cut flower. Cosmos bipinnatus ‘Sea Shells’ is an eye-catching, long-flowering choice for your garden that likes a position in full sun and moderately fertile, moist but well-drained soil.

Common problems with Cosmos 'Sea Shells Mix'

How to harvest Cosmos 'Sea Shells Mix'

Collect seeds from ripened capsules and store them in a dry, cool dark location for use the following year. Alternatively, allow the seed to self-sow, transplanting seedlings in the spring to more desired locations.

How to propagate Cosmos 'Sea Shells Mix'


Sow between March and May into trays of per-watered seed compost and cover with 3mm sieved compost. Keep between 15-25C until they have germinated. Once the seedlings are large enough to handle (produced 2 leaves) transplant into 7cm (3") pots and move to a cooler location to continue growing. Plant out once the threat of frosts have passed and space each plant 45cm (18") apart.

Special features of Cosmos 'Sea Shells Mix'

Attractive flowers

Attracts useful insects

Pot plant

Other uses of Cosmos 'Sea Shells Mix'

These stunning flowers make lovely additions to mixed flower borders or grown in containers in almost all garden styles. Suitable for use in coastal locations.