With a height of as tall as 48 inches and a width of about 18 inches, these are large plants that are spectacular in a flower garden. The fluted flowers with rolled petals have an unusual shape that always get a double take. The enormous flowers have petals 3 inches long that are set against thin, fern-like foliage. The flowers grow to 3 to 5 inches across. They are also one of the easier plants to grow, preferring neglect to a lot of maintenance. They will tolerate poor soils, rocky areas and drought. Cosmos Sea Shells make great cut flowers and tall, striking flowers for flowerbeds. The height of the plants makes them a perfect backdrop for smaller plants in the garden.
Keep the seeds moist as they germinate and plant in full sun. Thin out the seedlings 12 to 24 inches apart. Blooms appear about 10 weeks after sowing the seeds. To keep Cosmos Sea Shells blooming throughout the summer, deadhead them as the flowers fade. Taller stalks may need to be staked, particularly in windy areas. Seeds are packaged and germination tested for current year.
Blooms June through September
Grows to a height of 36 to 48 inches
Plant seeds at a depth of 1/8 inch
Germination is 10 to 20 days