If you want to attract butterflies to your garden, grow Yarrow seeds and bring beauty and butterflies! This Achillea Summer Pastel Mix is made up of a wide range of colors: pink, rose, orange-red, purple, gray, salmon and mauve. Yarrow is a perennial, upright flower that blooms from spring until fall. The flower heads are 3 - 4 inches wide, the Yarrow plants spread 18 - 24 inches and reach 24 inches in height. Yarrow Summer Pastels make a great addition to any perennial garden for mass plantings, borders, naturalized settings and cottage gardens. It also is a great cutting flower.