As rising temperatures, drought, and flooding threaten coffee farms, farmers and scientists have set their sites on a more climate-resilient bean. Turns out, they’ve been growing for more than a century. 

We are a coffee-guzzling planet, and 90 percent of all we drink comes from only 12 regions of the world. What happens when even half of those areas are devastated by rising temperatures, droughts, and flooding? 

We’ve already started to find out.

According to The Guardian, “Researchers analyzed the impacts of climate factors such as temperature, rainfall and humidity in the top 12 coffee-producing countries globally between 1980 and 2020. The study, published in the journal PLOS Climate, found that the frequency of “climate hazards” – suboptimal growing conditions due to extremes such as high temperatures – had increased in every region during that period. Five of the six most hazardous years occurred between 2010 and 2020.”

Though there are more than 120 varietals of coffee, almost all of what we drink comes from the two most widely grown—arabica and robusta. It turns out they are both pretty finicky about their growing conditions, requiring conditions that are neither too cold and wet nor too hot and dry. For growers of these beans, climate change could spell disaster. In fact, researchers warn that, by 2050, only about half of the current coffee-farming land will still be suitable for growing the bean. 

As climate change threatens all types of food farms, including coffee, the quest is on for resilient plant varieties. And growers have been paying closer attention to two candidates: Coffea stenophylla and Coffea liberica. 

Far from being fancy new lab-grown varietals, both plants have been hiding in plain sight for a century or more.

Coffea stenophylla: The forgotten bean

As early as the 1830s and likely for far longer, farmers in Sierra Leone were growing and exporting Coffea stenophylla.  In fact, by the 1890s, stenophylla “dominated the market” for coffee in Europe.

Stenophylla is notable for its ability to grow in higher temperatures at lower elevations. It also takes a bit longer to grow and has lower yields, which caused farmers at the time to replace the bean with the more productive robusta plant. By the late 1950s, stenophylla was all but forgotten by the world.

And yet the plant quietly kept growing in parts of Sierra Leone until researchers in 2018 “rediscovered” stenophylla growing wild.

Researchers are now exploring techniques to introduce stenophylla genes into arabica and robusta plants, creating new breeds with improved resistance to environmental stress. This crossbreeding approach holds promise for cultivating climate-resilient coffee beans capable of withstanding the challenges posed by a changing climate.

Coffea liberica: The Malaysian not-so-secret bean

Also native to West Africa, Coffea liberica never took off in most places of the world due to its larger beans with inconsistent sizes, making it harder to process. The processing struggles often translated into a less tasty brew, and that of course meant it was less popular all around.

In the late 1870s, however, coffee leaf rust was decimating robusta plants in Sri Lanka, Malaysia, and the Philippines. In those places, liberica plants became the primary replacement. And it’s been growing steadily in the area ever since.

While liberica is no longer the primary coffee grown in the area, and farmers still struggle with processing woes, the plant is still produced and sold in coffee shops around Malaysia and the Philippines, often in the form of blends with more popular varieties.

Like stenophylla, scientists and farmers have regained interest because of the plant’s higher tolerance for warmer temperatures and its resistance to diseases like coffee leaf rust.

Research is ongoing to explore the potential of liberica as a resilient alternative or as a genetic resource for breeding programs. By incorporating liberica genes into traditional arabica and robusta plants, scientists aim to develop coffee varieties that not only resist diseases and pests but also thrive in a changing climate.

Climate-resilient hybrids: The future of coffee farming?

In response to climate change, coffee farmers have limited options. They can plant more trees in areas that have been deforested to shade their crops and prevent water runoff. This is a crucial but slow process that will take decades to pay off. They can move to higher and higher elevations, assuming there’s access and available land. Or, they can try farming hardier species.

That’s where varietals such as Coffea stenophylla and Coffea liberica come in.  Not only can farmers plant and grow these species in most of the 12 growing regions, but scientists are also working to breed them with existing arabica and robusta plants to produce new varietals that benefit from the best qualities of each.

By blending the hardiness of stenophylla and liberica with the desirable flavors and yield of arabica and robusta, these hybrids aim to strike a balance between taste and resilience. 

Preserving biodiversity and cultural heritage

Remember those 120+ coffee species we mentioned earlier? We have only two main varieties now because, at least for a time, they produced the largest yields for the lowest price and were popular with consumers.

But monocropping is always short-sighted, acclimating us to a single type of a crop and leaving that same crop vulnerable to devastation. By reintroducing genetic diversity to coffee production, we may be able to prevent widespread crop failures—and a world without our beloved morning coffee.

In addition, in regions where stenophylla and liberica have historical roots, their cultivation can revive traditional coffee farming practices. Supporting these varieties not only aids in the conservation of indigenous knowledge but also empowers local communities by diversifying their agricultural options and creating opportunities for economic growth.

As climate change continues to reshape the coffee-growing landscapes, climate-resilient coffee varieties offer a beacon of hope against a coffeeless morning. Coffea stenophylla and Coffea liberica have been quietly growing out there for more than 100 years, our heroes in waiting.