Coffea arabica is a species of Coffea originally indigenous to the mountains of the southwestern highlands of Ethiopia. It is also known as the “coffee shrub of Arabia”, “mountain coffee” or “arabica coffee”. Coffea arabica is believed to be the first species of coffee to be cultivated, being grown in southwest Ethiopia for well over 1,000 years.
It is said to produce better tasting coffee than the other major commercially grown coffee species, Coffea canephora (robusta), because robusta cherries contain twice as much caffeine as arabica. Caffeine itself has a bitter taste, making robusta more bitter. C. arabica contains less caffeine than any other commercially cultivated species of coffee.
Wild plants grow to between 9 and 12 m tall, and have an open branching system; the leaves are opposite, simple elliptic-ovate to oblong, 6?12?cm long and 4?8?cm broad, glossy dark green. The flowers are white, 10?15?mm in diameter and grow in axillary clusters. The fruit is a drupe (though commonly called a “cherry”; interestingly, the plural form is simply “cherry” – used only when referring to the fruit of C. arabica – when referring to the actual cherry fruit, the appropriate plural is “cherries”) 10?15?mm in diameter, maturing bright red to purple and typically contains two seeds (the coffee seeds).
Originally found in the southwestern highlands of Ethiopia, Coffea arabica is now rare in its native state, and many populations appear to be mixed native and planted trees. It is common there as an understorey shrub. It has also been recovered from the Boma Plateau in South Sudan. C. arabica is also found on Mount Marsabit in northern Kenya, but it is unclear whether this is a truly native or naturalised occurrence.
The conservation of the genetic variation of Coffea arabica relies on conserving healthy populations of wild coffee in the Afromontane rainforests of Ethiopia. Genetic research has shown coffee cultivation is threatening the genetic integrity of wild coffee because it exposes wild genotypes to cultivars.
Coffea arabica accounts for 75-80 percent of the world’s coffee production.
C. arabica takes about seven years to mature fully, and does best with 1.0?1.5 meters (about 40?59?inches) of rain, evenly distributed throughout the year. It is usually cultivated between 1,300 and 1,500 m altitude,but there are plantations as low as sea level and as high as 2,800 m.
The plant can tolerate low temperatures, but not frost, and does best with an average temperature between 15 and 24 ?C. Commercial cultivars mostly only grow to about 5 m, and are frequently trimmed as low as 2 m to facilitate harvesting.?C. arabica prefers to be grown in light shade.
Drawing of Coffea arabica
Two to four years after planting, C. arabica produces small, white, highly fragrant flowers. The sweet fragrance resembles the sweet smell of jasmine flowers. Flowers opening on sunny days results in the greatest numbers of berries. This can be a curse, however, as coffee plants tend to produce too many berries; this can lead to an inferior harvest and even damage yield in the following years, as the plant will favour the ripening of berries to the detriment of its own health.
On well-kept plantations, overflowering is prevented by pruning the tree. The flowers only last a few days, leaving behind only the thick dark green leaves. The berries then begin to appear. These are as dark green as the foliage, until they begin to ripen, at first to yellow and then light red and finally darkening to a glossy deep red. At this point they are called ‘cherries’ and are ready for picking.
The berries are oblong and about 1?cm long. Inferior coffee results from picking them too early or too late, so many are picked by hand to be able to better select them, as they do not all ripen at the same time. They are sometimes shaken off the tree onto mats, which means ripe and unripe berries are collected together.
The trees are difficult to cultivate and each tree can produce from 0.5 to 5.0?kg of dried beans, depending on the tree’s individual character and the climate that season. The real prize of this cash crop are the beans inside. Each berry holds two locules containing the beans. The coffee beans are actually two seeds within the fruit; there is sometimes a third seed or one seed, a peaberry in the fruit at tips of the branches. These seeds are covered in two membranes; the outer one is called the “parchment coat” and the inner one is called the “silver skin”.
On Java Island, trees are planted at all times of the year and are harvested year round. In parts of Brazil, however, the trees have a season and are harvested only in winter. The plants are vulnerable to damage in poor growing conditions (cold, low pH soil) and are also more vulnerable to pests than the C. robusta plant.
A Coffea arabica plantation in S?o Jo?o do Manhua?u, Minas Gerais, Brazil.