Climate Change and Coffee Rust
Arabica, a higher quality coffee than Robusta grows in higher altitudes (microclimates). The combination of high altitudes and cool temperatures provide an ideal environment for coffee cherries to mature and for its sugars to develop. An increase in temperatures (climate change) means that suitable land for coffee growing could decrease. Indeed, by 2080, the number of environmental conditions for Arabica coffee to thrive is predicted to reduce by 85%. and while new areas may become suitable, they may be deforested or unsuitable.
Robusta’s ability to thrive in warmer temperatures has been suggested as an alternative to Arabica. However it is of lower quality. For myself, to simply replace Arabica varieties with that of Robusta is like putting band-aids on bullet hole problems.
Coffee Rust (La Roya)
In hand with climate change, is the issue of coffee rust which prospers in warmer temperatures. Coffee rust is a fungus that has had a significant impact on coffee production in Central America. It is a fungus that affects the margins of the coffee plant leaf; and then spreads upwards; the lower leaves then drop off and leave bare twigs.
The impact of this is that there are both over-ripe and under-ripe coffee cherries on the tree, as the fruit matures too quickly on rust affected trees. The sugars don’t have time to develop; therefore the fruit doesn’t ripen to its usual level. (Read the extended blog post about La Roya here)
“Survival of the fittest”
Only 3% of the coffee varieties that exist outside of Ethiopia (the natural birthplace of coffee), are being used; as such existing coffee varieties lack genetic variety to combat “new” diseases. If you think of Darwin’s “survival of the fittest,” Robusta is fitter/ more robust than that of Arabica.
The science and research needed to provide rust resistant varieties is lacking, “Unlike many other crop species, coffee has had very little research behind it” (Dr Timothy Schilling, executive director of the World Coffee Research institute (WCR).). While there are hybrids such as Sarchimor (Breed between arbaica and robusta) it does not taste very good (low cup score).
In combating coffee rust, preventative measures (such as pesticides) work to remove a producers ‘organic’ certification. This has flow on effects of preventing them from receiving higher prices.
Crop or organic certification?
But if you had a choice between losing your whole crop OR losing your organic certification. What would you do? In an industry, where some are living mouth to hand, be mindful that “organic certification” may denote form rather than substance.
By Karyan Ng
This is the eighth and final blog post in an eight-part introductory blog series about Specialty Coffee. If you know someone who would benefit from this foundations course – send them to the previous posts here. The contents of this blog series will be compiled into an e-book, a resource for those interested in specialty coffee, its origins and stories. Bean Market will continue blogging and writing about coffee. You can subscribe to the newsletter here. This blog series was not financially sponsored in any way. Thanks for reading.