Rhubarb chard and ruby chard are among the most popular varieties. Rhubarb chard has dark green leaves and reddish stalks, whereas ruby chard has a bright red stalk and deep red leaves tinged with green. The flavor of the two does not differ much. Some specialty markets carry rainbow chard. It features red, white, and gold stems that contrast beautifully with its glossy green leaves. This variety makes an attractive addition to salads. Be sure the stalks are tender and finely sliced.