Cornflower 39black ball39 produces pincushion flowers in a rich milk45chocolate shade that looks almost black on cloudy days drifts of this annual cornflower serve a double purpose adding drama to summer borders and wildlife gardens whilst attracting bees and butterflies a tall centaurea variety cornflower 39black ball39 also makes an excellent cut flower height 75cm 40303441 spread 30cm 40123441culinary information add petals to salads as a colourful g