The cultivation of coffee trees began in Ethiopia and were subsequently spread around the world, of which there are now many sub-species that exist through both natural selection and selective breeding. These coffee varieties have inherent traits that make them unique, such as resistance to disease, fruit yield, bean size and taste profiles. These traits are considered by the farmers when deciding which varieties to grow on their land, for example a high yielding coffee would be considered a desirable quality.
Arabica vs. Robusta
There are two main species of coffee that are in commercial production, Arabica and Robusta, with Arabica representing about 75% of the worlds production. Arabica's susceptibility to a disease called leaf rust has caused coffee growers to seek out new varieties that have a higher resistance, such as Robusta. Unfortunately the taste quality of Robusta is often uninteresting and woody, making it unsuitable for specialty coffee at this time.
Variety: a genetically distinct variation of a single species that may have different characteristics in plant structure, leaves or fruit.
Cultivar: same definition as 'variety' but indicates a genetic variation due to cultivation.
Varietal: refers to a specific instance of a variety, for example if one farm produces Bourbon, then that is the farms varietal.
Typica: This is the original variety that was cultivated, with all other varietals thought to be mutations or genetic selections of Typica. Generally a lower yielding coffee but an excellent cup with nice sweetness, cleanliness and smooth body.
Bourbon: A natural variation of Typica, Bourbon was first produced on Reunion Island, located off the coast of Madagascar, later being spread to the rest of the world. Bourbon has a yield of 20-30% more than the Typica variety and is known for its sweetness, complex acidity and balance in the cup.
Caturra: A high yielding mutation of Bourbon that was discovered in Brazil. Cup quality of this coffee increases with elevation, however the yield decreases. This variety is considered a dwarf or semi-dwarf because of its small shrub size, though it makes for much easier picking by hand. Cup characteristics are generally a nice bright acidity, low-medium body and a little less sweetness than Bourbon.
Villa Sarchi: Named after the town in the West Valley of Costa Rica where it was discovered. Another dwarf variety that is very high yielding and produces well at high elevations. Cup characteristics are a clean acidity and very fruit forward sweetness.
SL28/SL34: A highly prized variety that typically fetches a high price, selectively bred by Scott Laboratories in Kenya in the 1930's. Beans can be very large, producing a cup with distinct fruit flavour and a nice complexity. SL28 exhibits a better cup generally than SL34, both are very susceptible to leaf rust and grow better at higher elevations.
Ethiopian Heirloom: Most of the coffee grown in Ethiopia are the indigenous heirloom varieties that have resulted from cross-breeding different species as well as varieties. This has made coffee from Ethiopia to be some of the most unique and coveted from around the world. Depending on the coffee process, Ethiopian coffee can have tasting qualities that are floral, tropical fruit, sweet citrus, chocolate and lots of berries.
Catuai: A high yielding cultivar which originates from Agronomico do Campinas in Brazil in the 50's. A mutation of Mundo Novo and Caturra. It has since been cultivated throughout Brazil and in many regions of South and Central America. It's known for lower acid, high sweetness and high body in the cup.
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