Native to China and India, oranges (Citrus sinensis) have been cultivated in the United States since the early 1700s. Valued for their fragrant white flowers in the spring and nutritious fruit in late fall and winter, orange trees are suitable for U.S. Department of Agriculture hardiness zones 9 through 11. With good care, the tree grows to be approximately 20 to 30 feet tall and has a naturally well-rounded shape. Orange trees need full sun and well-drained soil to thrive