Home Gardening Cosmos, Seashells Mix Petals are like lightly fluted seashells. Flowers 3 across, petals lightly rolled like seashells in creamy and pastel white, pink, rose and carmine. Bright, colorful daisy-like blooms on tall stems with ferny leaves. GARDEN HINTS: Tolerates poor soil, heat and drought. Sow directly in the garden, where you want them to grow, after last spring frost. Grows best in full sun.