Citrus, << SIHT ruhs, >> is the name of a group of trees and shrubs which belong to the rue family. Some citrus fruits are oranges; grapefruits; lemons; mandarins, including tangelos, tangerines, tangors, and their hybrids; kumquats; bitter oranges; limes; citrons; shaddocks; and bergamots. Citrus trees grow wild in parts of India and southeastern Asia. The Chinese were the first to cultivate citrus trees, more than 4,000 years ago. These trees and shrubs have been grown in other parts of the world for their fruits for many years.
Citrus trees are thorny, but usually attractive. They are evergreen, with long, shiny, pointed leaves. The flowers are fragrant. Ripe citrus fruits may be green or yellow to orange-red in color. All citrus fruits are a type of berry that scientists call a hesperidium.
Citrus fruits all grow in rather warm climates. They grow best where there is almost no frost or wind. All grow in tropical regions, but produce better fruit in a slightly cooler climate. Citrus plants grow best in Arizona, California, Florida, and Texas in the United States. Citrus fruits are grown in greater quantity than any other fruit in the United States. Citrus fruits are valuable foods. They contain large amounts of vitamins and minerals. Citrus fruits are usually high in vitamin C.