Bachelor Buttons Polka Dot Mix (Centaurea cyanus), also called Cornflower, is an easy annual wildflower in blue, crimson, pink, and white, sold as a seed pack covering about 10 sq ft. At a glance Variety: Polka Dot Mix Cornflower (Centaurea cyanus), open pollinated Type: Annual wildflower Coverage: Pack covers approx. 10 sq ft broadcast (approx. 624 seeds) Planting depth: 1/8" Sun: Full to partial sun Spacing after thinning: 8" to 10" Height at maturity: 24" to 35" USDA zones: 3 to 10 Best for Cut-flower gardens; the blooms also dry well Pollinator plantings that attract butterflies and beneficial insects Cottage gardens and borders Drought-tolerant, low-fuss color Gardeners who want flowers that self-sow How to grow Sow in fall or spring at 1/8" deep in any adaptable soil, then thin to 8 to 10 inches apart; germination takes 7 to 25 days. Grow in full to partial sun with moderate water. Plants bloom from early spring into summer and freely self-sow for repeat color. About Grow Organic Grow Organic offers a wide range of organic gardening supplies, from seeds and fertilizers to tools and growing essentials, supporting home gardeners and small farms alike.