9 Citruses that you probably do not know
1. Citron (or Citrus Medica)
The fruit is the citron and comes from India. Cultivated since ancestral times, it was the first citrus arriving to the Mediterranean region, so it has great historical importance. It is indigenous from the slopes of the Himalayas and it arrived to Media (Iran) through Middle East, during the VII century b.C. First of all they were known by Greeks, around the 320 b.C, and then it went to Rome. Its is believed that it was the only citrus known to Greeks and Romans; but archaeologists confirm to have recognized lemons and oranges in fresco paintings in Pompeii from the I rd century. Nowadays it is rarely cultivated in Spain, so if we want to enjoy them, we would have to look for them in a greenhouse, although you can find them wild walking in the countryside.
2. Key lime (or Citrus aurantifolia)
Its fruit is the acid or bitter lime , lime from West Indies or real true lime, which is the smallest of the bitters, and usually have many seeds. It may be an hybrid between Citrus medica medica and another unknown Citrus. It requires a very warm and frost-free climate, that is why it is almost unknown in Europe. It is one of the most rustic citruses and it is also well cropped on poor lands. It is sometime crossed with lemon, and it is sometimes used as graft pattern.
3. Persian Lime (or Citrus latifolia)
It is the other bitter lime, most popular in Europe, but also rare, the fruit is a bit larger and seedless, it is grown in Brazil and Florida, and it is the denominated in Spain, Arabic lima árabe or limetero árabe. Its fruit or orange-lime has the size of an orange and slightly acidic juice. It was very popular in the Muslim Spain.
4. Indian sweet lime (or Citrus limettioides)
Its fruit is the sweet lime, Indian lime or Palestinian lime, quite widespread in the Middle East, India and America and different from the sweet Mediterranean lime.
5. Bergamot (or Citrus aurantium subespecie bergamia)
Description: Its fruit is the bergamot , and it is one of the breeds of bitter orange.
Cultivation and use: It has been known for several centuries in the Mediterranean but its origin is unknown. It is cultivated mainly in Italy (Calabria) for its aromatic rind: the essence is used for the fabrication of genuine water cologne, developed in Cologne (Germany), in 1676, by an Italian immigrant, and used to scent some English teas, as Earl Grey. It seems to come from an hybridization of bitter orange and others citrus, might be with the sweet Indian lime.
6. Tangor (or Citrus nobilis)
It is an hybrid specie between mandarin and orange, that comes from the Citrus sinensis backcrossed with Citrus reticulata. The fruit has a skin easily removable and it is well cultivated in Florida for its aromatic fruits.
7. Cumquat or kumquat (type Fortunella Swingle)
They are citrus very small, which are eaten whole (with rind). Its name is dedicated to a Scotch horticulturist called Robert Fortune (1813-1880), he lived for few years in China and introduced the crop of tea in India and Ceylon, and brought the Cumquats, in 1846, to England.
The most well-known species in Europe is the Fortunella Margarita Swingle, almost unarmed shrub, with lanceolate leaves, almost whole (with small festoons on the top), of pale color and marked out in the back, solitary flowers , with (3)5(6) petals, welded by filaments in various groups, oval fruits, clearly longer than wide, 2,5-3,5 x 2-2,5 cm, with (2)3-6(7) sections. The fruits are prepared in jams. It is also cultivated as ornamental plant, for it pleasant foliage, and because with its mature fruits it is extremely decorative.
We can also find hybrid citrus from lemon, the limequat and with mandarin, the mandarinquat, with characteristics similar to cumquat.
8. Buddha hand (Citrus medica var. sarcodactylis)
Citron grows in shrubs or small trees with long and irregular branches covered in thorns. Its large and oblongs leaves are pale green and measure up to 10 to 15 cm. Its withe flowers are dyed in purple on the outside and grow in fragrant groups.
The fruit has a thick skin and just a small amount of acidic pulp (if any), and it has not got juice neither sometimes seeds. It is very fragrant and it is mainly used by Chinese an Japanese people for perfuming rooms and personal items like clothing.
The skin of the fruit can be caramelized. It is also used in cooking its skin and its pith, which is not as bitter as in other citrus.
The origin of the of Buddha’s hand has been tracked to the northeast of India and China.
The tree is sensitive to freezing, intense heat and drought. Areas such as Southern California and inland valleys are considered ideal for growing. The trees can be cultivated by cuttings of branches ranging from 2 to 4 years.
9. Citrus australasica or finger lime
The finger lime is an understorey shrub or small tree of lowland subtropical rainforest in the coastal border region of Queensland and New South Wales (Australia).
The plant is from 2 to 6 metres in height. Leaves are small, 1-5 cm long and 3-25 mm wide, glabrous, with a notched tip and crenate towards the apex. Flowers are white with petals 6 to 9 mm long. The fruit is cylindrical, 4-8 cm long, sometimes slightly curved. Coming in different colors, including pink and green.
The finger lime has been recently popularised as indigenous food. The globular pulp has been compared to a “lime caviar”, which can be used as a garnish or added to various recipes. The fresh pulp has the effect of a burst of effervescent tangy flavour as they are chewed. The fruit juice is acidic and similar to the lime. Marmalade and pickles are also made from this fruit. The peel can be dried and used as flavouring spice.
There is a wide range of colours for the finger lime, including green, yellow, orange, purple, black and brown. It probably has the most extensive variety of colours of any of the Citrus species.
Commercial use started in the mid- 90s in stores of jams, elaborated from wild fruits. By 2000 it was being sold in restaurants, including the export of fresh fruit.
Lately this citrus has been recently grown on a commercial basis in Australia in response to high demand of the fruit. There is an increasing range of genetic selections, which are budded onto Citrus rootstock. With the sudden high market demand for the fruit, the primary source of genetic material for propagation, has been selections of wild stock.
In cultivation, the plant is grown in much the same way as other citrus species. It may be subject to some pests and diseases , requiring pest control in cropping situations. Doctor Andrew Jessop’s research int fruit fly, has concluded that fingers limes are not host plants to fruit flies and as such are not a not a quarantine risk to importing countries.
A research conducted in the 1970s indicated that a wild selection of C. australasica was highly resistant Phytophthora citrophthora root disease , which has resulted in a cross-breeding program with finger lime to develop disease-resistant citrus rootstock.
The Commonwealth Scientific and Industrial Research Organization(CSIRO) has also developed some Citrus hybrids by crossing the finger file with standard citrus species.