Two species of coffee are grown commercially. Coffea canephora, or robusta coffee, is an often bitter species that is usually considered low quality and is used as a filler in cheap grocery store coffee. The higher quality arabica coffee, Coffea arabica, is an understory tree or shrub which naturally grows in shade. However, mostly with an eye toward profit, there has been a movement to find ways to grow arabica coffee in the sun.
Coffee is grown on nearly 10 million hectares in tropical regions around the world, areas that also harbor high levels of biodiversity. In the 1990s, farmers were encouraged to replace traditional shade grown coffee with sun cultivation in order to increase the yield of their coffee. In sun coffee systems, there is little or no canopy cover, and coffee trees are planted at high densities. In Latin America, 1.1 million of the 2.8 million hectares in coffee (41%) were converted to sun cultivation (Rice and Ward 1996). The impact of deforestation and conversion of shade coffee to sun coffee on biodiversity in these regions is much greater than the absolute levels of destruction would indicate.
While older arabica coffee varieties traditionally grown in the shade did not do well in the sun, they were replaced by hybrids that could withstand the sun and had more resistance to introduced diseases. But sun cultivation also has many other negative environmental impacts:
- In shade plantations, dead leaves from the overstory trees provide nutrients to the coffee. In sun plantations, these nutrients are not available, so fertilizers must be used, especially nitrogen (since many traditional overstory trees are nitrogen-fixing legumes). Sun coffee farms leach triple the nitrates into the local watersheds than shade farms.
- There are fewer weeds in shade plantations, both because of the shade itself and due to the fallen leaves from shade trees acting as a natural mulch. Herbicides are needed to control weeds in sun plantations.
- Soils in sun plantations are more exposed to the elements, particularly drenching rains typical of tropical areas. This leads to erosion of topsoil, and the leaching of chemical fertilizers, pesticides, and herbicides into local watersheds. Soil erosion and acidification and water pollution are serious consequences of growing coffee on sun plantations.
- Coffee plants in sun plantations grow faster and age more quickly than those grown in shade, and therefore must be replaced more often. Sun-grown coffee trees are typically productive for less than 15 years, while shade-grown coffee trees may yield for 30 years or more.
You can read more about the benefits of growing coffee in the shade in this post.
Donald, P. F. 2004. Biodiversity impacts of some agricultural commodity production systems. Conservation Biology 18:17-37.
Rice, R. A., and J. F. Ward. 1996. Coffee, conservation, and commerce in the Western Hemisphere. Smithsonian Migratory Bird Center and National Resources Defense Council.
Revised on October 22, 2016
Coffee grown in India is entirely shade-grown and very environmental friendly. Infact, to a layman, coffee plantations look like forests. Bird life thrives on these plantations.
Most of these plantations are at an altitude of 2500-4000 feet.
What are altitudes at which 'sun' coffee is grown?
If the sun is robusta, it can be grown at lower altitudes, say 1000 meters. Arabica varieties of sun coffee are grown at the nearly the same altitudes as other coffee. However, the goal of sun coffee is higher yield, so in addition to growing in monocultures in the sun, producers want to be able to harvest by machine. This is more difficult in rugged terrain, which is more common at higher altitudes.
I am planning an in-depth look at coffee in India when I have more time, because the coffee systems often do preserve a lot of biodiversity. Indian coffee is not very common in the U.S., especially in stores and retail outlets. But I want to cover it anyway! Thanks for stopping by Bharat!
I'm currently on a coffee farm in south kona on the big island of hawaii. we are an organic farm with lots of shade and lots of non-shade coffee. This article mentioned that herbicides are need to control weeds on sun plantations" and this is simply not true for the entire world. We do not use non-organic chemicals on our farm and we weed by hand. Also, it was mentioned that sun trees need to be replaced about every 6 years and this is simply not true. We have sun trees that are 40 years old on our farm. Plus, shade coffee trees look more full at the same time as sun coffee trees, but sun coffee trees, as mentioned, produce a higher yield. I am for increasing biodiversity across the globe, but why is coffee singled out? yes, it's the second most traded commodity, but other crops should also use shade.
Thanks for your comment, Darren. In speaking of "sun coffee" in this context, it is generally meant to mean the large, technified farms. These big plantations in particular are not hand-weeded, but use herbicides as well as other chemical inputs such as non-organic fertilizers. This push to produce artificially higher yields is one reason trees are replaced much more often — when they produce less they don't give a good enough return on investment (cost of all the inputs); often these trees are also of varieties that do better in sun and are high-yielding, but may not be as long-lived as other varieties. In this context, the statements are indeed true — for more information you can read the material at the Smithsonian Migratory Bird Center and World Wildlife Fund.
Why single out coffee? Because unlike the majority of major crops in the world, it is essentially a forest crop, and expansion of technified coffee nearly always involves deforestation. And it grows in tropical areas that are frequently the world's biodiversity hotspots. Browse the archives here, and you will find a lot of information and links that make this case very strongly.
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