Bicolour purple and bicolour lilac flowers are the hallmark of Smokey Amethyst Dahlias. Some are light against dark, and the other half are dark against light, so the contrast is very attractive both in the garden or as cut flowers. These so-called Decorative Dahlias grow to 70cm (28″) tall, and are hardy to Zone 4. Grow in full sun. Each package contains three tubers.