Coffee traces its origin to a genus of plants known as Coffea. Within the genus there are over 500 genera and 6,000
species of tropical trees and shrubs. Experts estimate that there are anywhere from 25 to 100 species of coffee plants.
The genus was first described in the 18th century by the Swedish botanist, Carolus Linneaus, who also described Coffea
Arabica in his Species Plantarum in 1753. Botanists have disagreed ever since on the exact classification, since coffee
plants can range widely. They can be small shrubs to tall trees, with leaves from one to 16 inches in size, and in
colors from purple or yellow to the predominant dark green.
In the commercial coffee industry, there are two important coffee species —
Arabica and Robusta.
Varieties: Bourbon, Typica, Caturra, Mundo Novo, Tico, San Ramon, Jamaican Blue Mountain
Coffea Arabica is descended from the original coffee trees discovered in Ethiopia. These trees produce a fine, mild,
aromatic coffee and represent approximately 70% of the world's coffee production. The beans are flatter and more
elongated than Robusta and lower in caffeine.
On the world market, Arabica coffees bring the highest prices. The better Arabicas are high grown coffees — generally
grown between 2,000 to 6,000 feet (610 to 1830 meters) above sea level — though optimal altitude varies with proximity
to the equator.
The most important factor is that temperatures must remain mild, ideally between 59 - 75 degrees Fahrenheit, with about
60 inches of rainfall a year. The trees are hearty, but a heavy frost will kill them.
Arabica trees are costly to cultivate because the ideal terrain tends to be steep and access is difficult. Also, because
the trees are more disease-prone than Robusta, they require additional care and attention.
Variety: Robusta
Most of the world's Robusta is grown in Central and Western Africa, parts of Southeast Asia, including Indonesia and
Vietnam, and in Brazil. Production of Robusta is increasing, though it accounts for only about 30% of the world market.
Robusta is primarily used in blends and for instant coffees. The Robusta bean itself tends to be slightly rounder and
smaller than an Arabica bean.
The Robusta tree is heartier and more resistant to disease and parasites, which makes it easier and cheaper to
cultivate. It also has the advantage of being able to withstand warmer climates, preferring constant temperatures
between 75 and 85 degrees Fahrenheit, which enables it to grow at far lower altitudes than Arabica.
It requires about 60 inches of rainfall a year, and cannot withstand frost. Compared with Arabica, Robusta beans produce
a coffee which has a distinctive taste and about 50-60% more caffeine.