Shade Grown Coffee


Inaccurate memes can be hard to correct. We’ve all heard, for instance, that “coffee is the second most traded commodity after oil.” 

Over the last few years, that one has largely been debunked, but like a weed in the garden, we still see it periodically. 

There is another meme circulating in coffee sustainability circles that requires clarification:

By 2050, half of the land suitable for coffee becomes unsuitable, and the demand for coffee will grow to be 2x what it is today. You do the math.

 1st: “Half of the suitable land becomes unsuitable by 2050…”

 “Suitable land” here refers to all land on the planet that is suitable or capable of coffee growing. It is not all the land currently under coffee cultivation. Turns out, even if we lose 50% of the “suitable land”, the remaining suitable land is way more than is necessary to fill a 2x, 3x, or 4x increase in demand. (Of course, it’s pressure for suitable farmland driving deforestation and other problems…. but that’s a topic for a different article.)

 I’m in no way saying that losing half of the suitable land will have no impact on farmers. If land becomes unsuitable for coffee trees in a coffee-growing region, the impacts will be (are) devastating. I’m just saying, roasters will always be able to get their beans. Always.

 2nd: The brilliance of the research from this meme was the clarity it brought to the various agro-climatic zones (ACZ) where coffee is grown. The research mapped each ACZ and provided estimates of how each zone fairs with climate change. The 5 ACZs described in Bunn’s WCR/CIAT research were: Hot/Dry; Hot/Wet; Constant; Cool/Dry; Cool/Wet. Each one of these ACZs changes with climate change, but in different ways. (Hot/Dry is the most vulnerable. Many of our favorite regions fall into this category.)

Screenshot 2022 05 09 At 09.09.44
Source: Research document: Multiclass Classification of Agro-Ecological Zones for Arabica Coffee: An Improved Understanding of the Impacts of Climate Change

 3rd: If shade is added to the models, nowhere near 50% of suitable land is lost.

 Those three points are key for those making long-term coffee investments and developing strategies designed to maintain current coffee supply chains.

 The 2 big problems that climate change presents to coffee farmers, then, are:

  1.  Who pays for the 30%-40% reduction in yields that a farmer experiences by adding shade? (Shade reduces the photosynthesis and productivity of the plant.
  2. Drought

Turns out, even if we lose 50% of the “suitable land”, the remaining suitable land is way more than is necessary to fill a 2x, 3x, or 4x increase in demand.

 Nothing grows without water. The coffee bloom is triggered by rainfall.

 Here’s where F1 hybrids come in. The F1s are proving to be high performers under shade. It’s possible to make up for some of the lost production due to less sunlight with the introduction of certain F1 hybrids. 

 But F1s for drought tolerance… Stenophilla, which is a different coffee species, has drought tolerance and could be crossed in an “interspecific” breeding effort to get those characteristics into the Arabica species, though we are likely decades away from being able to test anything in the field. Even more interesting to me, the new mother population of Arabicas recently discovered in Yemen (Yemenia) may provide the genetics for more drought-tolerant coffee trees that could be used outright or in conjunction with a breeding program. 

 Interspecific is breeding digression:

 Typically, different species can’t produce offspring or, if they do, are sterile. But it sometimes happens naturally, as it did with the Timor Hybrid that was the genetic bridge that brought Robusta genes into Arabica –the sarchimores and catamores. Interspecific breeding also happens artificially by exploiting a rare genetic defect, male sterility (no pollen), and in coffee, this was recently done to create something that’s been called an “arabusta.” The Arabusta is not the end goal but rather is a vehicle for bringing the genetics of the species Coffea canephora (Robusta) into Arabica varieties. 

 But let’s temper that optimism with some reality: 

 1) “Drought tolerance” hasn’t even been defined for a coffee tree yet. There’s no target for a plant breeder to even aim at yet. 

 2) When a plant is “drought-tolerant” this doesn’t mean it’s a cactus and thrives in drought conditions. It means it could produce “more” coffee in drought conditions than would otherwise be possible, but it will mostly mean that the plant has the stuff to survive a drought. It’s not that it will produce enough coffee to protect the producer’s economic well-being. 

There is only one known strategy for dealing with drought conditions that have proven to work: irrigation. This tells me that if the Hot/Dry ACZs become drought-ridden (a big swath of central America is currently experiencing a multi-year drought), it will be the larger, professional operations that soldier on. The ones that are able to invest in irrigation. The subsistence smallholders will likely need to find a new cash crop.

When someone indicates that climate change will threaten their ability to buy a cup of coffee in the future, they are not entirely wrong, however. The diversity of coffee growing origins is threatened. Many of these regions, punished by years of low prices, pests, coffee rust, and even political unrest, have resulted in reduced production. El Salvador production has dropped by nearly 80% since 1993.

The regenerative agriculture movement, combined with the ubiquitous “net-zero” commitments, will likely result in a global increase in shade-grown coffee. The benefits of this are undeniable. Trees can be an additional source of income, can help keep moisture in the soil, and contributes to biodiversity above and below the soil. But a rush to add shade without considering the long-term impacts on yield also threatens global coffee producers. Yield reduction results in an increase in the cost of production. There are lots of folks lining up, ready to pay for trees. But who is going to pay the increased cost of production?  

If the past is any indicator of the future, producers will be left with the check.

Feature image by: User:Anand.osuri – Wikimedia Commons


  • Greg Meenahan


    Greg Meenahan’s work focuses on reducing systemic barriers to human development and prosperity. Bringing people and organizations together to achieve social, environmental, and economic impact for disadvantaged people, his experience crosses social safety net programs in the US, literacy development in Guatemala at Child Aid, agronomic and genetic research at World Coffee Research, carbon reporting for Falcon Coffees, and program development at the Partnership for Gender Equity. His articles appear in Roast, Standart, and Bartalks.


  1. A lot of ground covered here and some good points made!
    A couple of things:
    Bunn et al’s work was funded by WCR, but in fact they no longer use the climatic categories thus established. A key problem with that sort of analysis is that it depends on long-term means rather than extremes and generally the models are a poor fit to the data.

    Nissan et al., [(2019) WIREs Climate Change DOI: 10.1002/wcc.579] are very critical about the short-comings of modellers as is Walter Baethgen of IRI who gave a good webinar on this subject for WCR

    Based on the Bunn study, the 2017 WCR Annual Report declared that when monthly maximum temperature exceeds 32°C for the hottest month, coffee zones become unsuitable. This is simply not true as shown by Rigal et al. (2020) Agric. Syst. 177.

    Shade is a massively complex issue but it is true that more shade means lower yields, though this might be offset to some extent by higher quality. The real problem is that coffee zones are so heterogeneous that it is impossible to give clear advice. Indeed, what might work well in one part of the ENSO cycle, may not work so well in the other extreme.

    Equally, organic coffee will tank yields. The best info on this (by IISD) shows on average yields are about half conventional. So this cannot be a scalable solution.

    Finally, there is intense interest in net-zero now, but nobody has convincingly shown how it can be done at reasonable cost … dealing with hundreds of thousands of scattered smallholder farmers, training, monitoring, measuring over decades, permanent disposal …it’s simply not a cost effective route to carbon sequestration.
    Some of this stuff is covered in Ken Davids’ new book, which is a great read!

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