The seed type grapefruits such as the Duncan White cultivar have more flavor than the seedless March grapefruit. The Duncan White Grapefruit tree can survive temperatures that drop down into the twenties F., the seed preserve causing it to be more cold hardy. The grapefruit is considered to be a mutation of the pummelo and the pigmented grapefruits all are mutations from other grapefruit plants. Duncan White grapefruit plants have an outstanding flavor and aroma and only a few seeds.