Yarrow, Bloowort F2 Summer Pastels Mix. A perennial summer flower with warm pastel tints evoked by the sun. Summer Pastels can grace borders for many years. An excellent cut flower for both fresh and dried forms. Once in a vase the flowers fill the room with pleasant summer fragrances. A traditional favourite. Sow in a greenhouse or in the garden in seedbeds, prick out, and transplant.