Perennial herbs, there are huge rod-shaped root, stem erect, much branched, 1.5 2 m tall, stout. People see it as a generous, the symbol of the rich. Design and color is generally have yellow, red, or purple, dahlias in flowering long popular, from summer to autumn, continuous bloom, each flower can continue to open a month, flowering last for six months. Sexual xi wet afraid of water, xi fertile fear of excessive, xi sun shade, like a cool afraid of hot.