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Cosmos bipinnatus 'Seashells mixed'

cosmos

Eventual height & spread

Cosmos bipinnatus 'Seashells mixed'

cosmos

  • approx 40 seeds
  • £2.99
  • available to order from summer
Delivery options
  • Seed Packets (only) £2.99
  • Position: full sun
  • Soil: moderately fertile, moist, well-drained soil
  • Rate of growth: average
  • Flowering period: June to October
  • Hardiness: half-hardy annual


This heirloom Cosmos from the 1800s showcases tubular-petalled blooms reminiscent of sea shells in a beautiful mix of white, pink, rose, and crimson. The tall, bushy plants feature delicate, lacy fern-like foliage that adds a fine texture to garden beds.

Cosmos bipinnatus 'Seashells mixed' bloom all summer long, providing a stunning backdrop when planted in drifts or groups, and for best results, offer some support, such as growing them between perennials, to maintain their upright habit.


  • Garden care:
    Seedlings should be potted up and grow on under glass until all risk of frost has passed and they can be planted outside in a well-prepared bed. Pinch out the growing tips to encourage bushier growth, and feed at regular intervals throughout summer with a high-potash fertiliser. Taller plants may need supporting with brushwood stems in exposed positions.


  • Sowing instructions:
    In early spring, sow seed shallowly in seed trays and keep under glass, transplanting them into individual pots when large enough to handle. Harden off before planting outside after the frosts. Alternatively, sow in-situ in mid- to late spring in a well-prepared bed and thin the seedlings out as they grow to allow approximately 30cm between each.


  • Sow: March to May
  • Goes well with