Orange (scientific name: Citrus sinensis English: orange), is the fruit of the orange tree of the genus Citrus, also known as yellow fruit, citrus, golden ring, and Liuding. Orange is a kind of citrus fruit with high edible and medicinal value.

Oranges originated in Southeast Asia. Orange trees are small trees. The fruit can be peeled and eaten with its flesh, and the flesh can be used as a seasoning or addition to other foods.

The cultivation of oranges has a long history, and its peel contains aromatic scent, which the ancients used as a fragrance substitute. The Western Han Dynasty tombs unearthed from Mawangdui, a suburb of Changsha, Hunan Province, have seeds of the genus. According to the text, it is considered that the seeds of the orange - thicker and slightly angular, the color has turned gray - think that it was used as a fragrance to bury and preserve one of the complete materials of the body. The seeds and other similar items are placed on the west side of the acupoint, while the food is placed on the east side.

The growth and flowering of oranges is closely related to temperature, sunshine, moisture (humidity), soil and environmental conditions such as wind, altitude, topography and aspect. These conditions affect the maximum number of temperatures. Even temperatures with a difference of °C sometimes have very different results. The most suitable temperature for orange growth is ~37 °C. When the flower buds are differentiated in autumn, the temperature of day and night is required to be about 20 ° C and about 10 ° C respectively. Too low temperature will cause the orange to be frozen. In addition, oranges are tree species that are more resistant to negatives, but good quality and high yields still require good sunshine. Generally, the areas with annual sunshine hours of 1200 to 2200 hours can grow normally.