It was over a year ago when I did an overview of coffee growing in Africa, and since then most of our African coffee discussions have been about Rwanda or Ethiopia. I’d like to focus on Tanzania, as a prelude to an upcoming review.
Tanzania grows both arabica (70%) and robusta. The majority of coffee is grown by small farmers, typically as one of several cash and subsistence crops; coffee is often grown under banana trees. Much of it is passive organic. The rest comes from nationalized estates that have been rehabilitated in recent years after much neglect. Coffee is a major crop in Tanzania and important to their economy.
Most arabicas are grown in the north, near the Kenyan border, on the slopes of Mt. Kilimanjaro and nearby Mt. Meru. They may be called Kilmanjaros, Moshis, or Arushas, and tend to be brighter and a little more acid. Coffees called Mbeyas or Pares are arabicas grown in southern Tanzania, between the rift lakes of Lake Tanganyika and Lake Nyasa, and generally have more body.
In the early 1970s, coffee berry disease and coffee rust began to attack coffee crops in east Africa. The larger Tanzanian holders that could afford to do so used pesticides, which had little of the desired effect, but decreased biodiversity. Part of Tanzania’s is ambitious plan to improve coffee production involves replacing all their coffee trees to more disease-resistant types. This project has been going on for about ten years now, and millions of disease-resistant coffee plants have been planted. As many of these trees were very old, this was not as wasteful as it might seem, and if it helps prevent the use of pesticides, or other exploitation of the environment due to an inability for small holders to make a living growing coffee, than it is a worthwhile mission.
One more problem in the region is water. With snow caps on the mountains diminishing (global climate change is a factor), farmers are struggling with irrigation issues, especially at Kilamanjaro. Some of these issues are being addressed by various organizations. KILICAFE is the Association of Kilamanjaro Specialty Coffee Growers; they have a set of sustainable company standards which include some environmental and biodiversity standards. See their web site for photos of coffee farms in their various regions (they include farms outside the Kilamanjaro area). Because deforestation also contributes to a lack of rainfall, sustainable farming methods will — one expects — become more and more important to the Tanzanian coffee industry.
Tanzania is rich in biodiversity. Most of the familiar Serengeti National Park is in Tanzania, on the border and sharing some land with neighboring Kenya. The crescent-shaped mountain ranges extending from Meru and Kilamanjaro in the north to Mbeya in the south are known as the Eastern Arc, rich in endemic species (for example, 43 butterflies, 96 species of vertebrates, and 800 plants are found no place else on earth). Two new species of coffee have been found recently in the Eastern Arc, Coffea bridsoniae and C. kihansiensis. The Pare Mountains are part of the Eastern Arc.
Any discussion of Tanzania coffee would be incomplete without mentioning peaberries. The fruit of a coffee plant, known as a cherry, has two flat-sided coffee seeds (beans) inside. A peaberry is just a fused bean — a small, round bean with a cleft down the middle, caused by the lack of fertilization of only one of the two ovaries of the coffee flower. Since about 5-10% of coffee cherries produce peaberries, why are so many Tanzanian coffees sold as peaberries? Nobody is sure how this marketing niche began, but you can read an excellent essay, the Tanzanian Peaberry Mystery, at Coffee Review.