Arabica and Robusta
Coffea is an evergreen shrub belonging to the Rubiaceae family. Today there are a few dozen known Coffea species although essentially there are only two of interest: Arabica and Robusta. These are the ones most widely cultivated as the others cannot be used for food purposes and thus are not of interest.
One of the main features of this plant is that the weather conditions it requires are found in tropical/equatorial areas (between the Tropic of Cancer and the Tropic of Capricorn) and thus this is where most coffee-growing countries are located.
It needs a mild climate, from 15° to 25° C, with substantial rainfall; its worst enemy is frost. It requires soils rich in nourishing mineral salts like those found in the tropical rain forests or volcanic lands.
Arabica plants prosper at an altitude of up to 2000 m. On the other hand, since the notably stronger Robusta can withstand thermal shocks, diseases and parasites much more easily, it can even grow in the plains, up to 800 m: indeed, this is why it is called “Robusta”.