Like other species of the exact origin of citrus mandarin is very uncertain, but is believed to be the north-east of India and China, south-west.

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Mandarin – Mandarin English – Italian and Spanish Chu Ju, or Chieh – Chinese Mikan – Santara or Suntara Japan – India
The tangerine has probably been cultivated in China for years several thousand years, and the first reference to this fruit goes back to the 12th century BC.
From his home region, tangerine spread in most of Southeast Asia, and other parts of India. By the tenth century, the mandarin is widely cultivated in the southern prefectures of Japan.
The origin of mikan or Satsuma unshiu back to the early 15th century.
Until recently it was believed that they originated from the Chieh Tsao (or Tsochu) tangerine but is now considered as a variant of Bendiguanchu, another local mandarin Wenzhou, Zhejiang Province, China, probably 1000 years ago. (Unshiu is a corruption of Wenzhou Japanese.)
It took more than 400 years before distribution worldwide tangerine be initiated when two varieties of mandarins Guangzhou (Canton) were imported to England by Sir Abraham Hume in 1805.
From this introduction trees were sent to Malta, then not close to Italy, it is believed that the Mediterranean mandarin evolved under cultivation in Italy shortly after.
Tangerine trees and their hybrids are usually the coldest hardies of all citrus grown commercially, although some, like the Temple tangor, which are less resistant than oranges.
However, the fruits of mandarin suffer more damage than most oranges and grapefruits.
The tangerine has a wide range of adaptability and grown in the desert, semi-tropical, and subtropical Mediterranean climate.
However, the different varieties of mandarins are very specific in their climatic requirements for the production of good quality. For example, the Ponkan and Tankan Dancy best fit semi-tropical conditions, and rarely occur near the Satsuma (unshiu) mandarin, which is more productive and reaches its maximum quality only in regions with cold winters.
The most demanding variety of mandarins in their climatic requirements is probably the Clementina, who still has a very restricted distribution, limited almost exclusively to coastal areas of Morocco, Spain, Corsica, and in the recent past in South Africa, Argentina, Uruguay, and Chile.
Mandarins, namely the Mediterranean and Dancy tangerine – and hybrids tend to switch to light when large fruit crops are followed by tiny light crops of large fruit, low quality.
Often, the other varieties are recommended as pollinators to promote better fruit set, while several agricultural practices such as banding stems, spraying growth regulator and hand thinning, are used to influence the behavior of uneven development.
Features shared by nearly all tangerines are its relatively short harvest season and their susceptibility to damage during harvesting, packaging, and transport to market.
The crust is fragile and sensitive to diseases with a tendency to swell, while internally the meat loses acidity and juice and becomes dull if not on the tree for a relatively short period after reaching maximum maturity. However, if handled with care mandarins can be stored successfully for several weeks or more.
Referred to a variety of names, probably evoked by advertising executives, ranging from the “soft-citrus” and “kid glove” to “zipper skin” and “easy peeler” mandarins have been appreciated for its distinctive fine and sweet
flavor. However, ease of peeling, the most common and famous.
The name “tangerine” is often synonymous with tangerine, especially in the United States, where it was used for the first time along with the variety of Dancy.
Later spread to other similar tangerines with reddish-orange tones in the shell. However, there are significant contradictions: some varieties of color no more than oranges are known as tangerines. To complicate matters, it was common in Europe to refer to “easy peelers” as mandarins. Fortunately, this is no longer the case, and perhaps the time has come to refer to all citrus skin loose as tangerines, specific name prefix, for example, Satsuma tangerines clementines and mandarin.
Although mandarins are widely distributed, annual world production remains modest at about 13 million tonnes compared with oranges to 51.5 million tonnes.
However, during the last decade have increased in importance to a much faster rate, production almost doubled, while oranges increased from 44.5 million tonnes in the same period. Nowhere is this more evident than in Western Europe, where the availability of mandarins in the last decade is such that there is no time of year when fruit quality is not on offer at the retail level.
There have been several attempts to catalog the mandarins in group classes or different species which follows here is a modification of RW Hodgson:
Citrus unshiu: Satsuma mandarins or unshiu
Delicious Citrus: Tangerine Mediterranean Citrus nobilis: The King of Citrus reticulata Tangerine: Tangerines Tangerines small fruit common: for example, red tangerine, and Nanfengmiju Bendizau
The first three groups are well-defined varieties of mandarin small but clear.
The fourth is a very wide collection of varieties, hybrid natural or man-made, many of them. The fifth includes many varieties of importance in East Asia for its fruit and others used as citrus rootstocks in several countries.
I have always pfrrereed tangerines to oranges NO wonder!!!! My eldest has been into blending essential oils since she was 14 and this is one of her favorites to add for uplifting I love it mixed with geranium and a little cinnamon essential oils to perk me up!!!YOUR photos are marvelous darling..filled with inner glow and tangerine joy!!!