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  • History
    • Topic XVIII

    What lies ahead

    Coffee is grown on 12.5 million hectares by 12.5 million farms, from two species out of a hundred and thirty, in a climate band that warming is already shrinking. This plate takes stock of what is measured (the 2021 frost, the 2024 drought, rust, the record prices of 2025), of what the models project for 2050, and of the responses under way: migration to altitude, agroforestry, irrigation, F1 hybrids, genomes, wild species, gene banks, the European regulation on deforestation, coffee without the bean. It draws on peer-reviewed articles (Bunn 2015, Ovalle-Rivera 2015, Moat 2017, Davis 2019, 2021, 2022, Kath 2020, Grüter 2022, Salojärvi 2024, Yang 2026), on institutional reports (USDA, ICO, WCR, Crop Trust, Conab) and on Marco's unpublished manuscript (LC ch. 2, 4, 16, 18, 21), and each time distinguishes the level of evidence.

    Color photograph of a twig of Coffea stenophylla grown in a greenhouse, with long, narrow leaves ending in a fine point, darker and more tapered than those of the Arabian coffee plant.
    Twig of Coffea stenophylla in the Berlin botanical gardenJi-Elle, February 16, 2018, CC BY-SA 4.0

    The 17 sections of this plate

    Each section has its own page. The first sentence says what you will find there.

    1. 01The specifications of an understory plantThe arabica coffee plant requires an annual mean of 20 to 25 °C, tolerates minima around 15 °C and maxima around 30 °C, and cannot withstand frost: the tree dies between minus two and minus three degrees.
    2. 02What the climate is already doing: rust, frost, droughtThe first signal was not a temperature but a fungus.
    3. 03What the models forecast for 2050The first peer-reviewed global projection is that of Bunn, Läderach, Ovalle-Rivera and Kirschke, published in Climatic Change in 2015.
    4. 04First answer: go up, shade, irrigateProducers do not read models, they move nurseries.
    5. 05Mechanizing: what the machine compensates for, and where it cannot goIn hand-picked coffee, harvest is the heaviest item in the cost of production.
    6. 06Second answer: F1 hybrids and the industrialization of breedingAn F1 hybrid is the first-generation cross between two genetically distant parents, typically a resistant line derived from the Timor Hybrid and a wild Ethiopian or Sudanese accession; it combines vigor, yield and resistance in proportions that cannot otherwise be obtained.
    7. 07Third answer: reading, then editing genomesIn April 2024, Salojärvi and coauthors publish the arabica reference genome in Nature Genetics.
    8. 08What happens under the treeThis plate is about shade, altitude, irrigation, varieties.
    9. 09The reserve of forgotten speciesThe genus Coffea has numbered 130 described species ever since Davis and Rakotonasolo added six from northern Madagascar in Kew Bulletin in 2021 (C. callmanderi, C. darainensis, C. kalobinonensis, C. microdubardii, C. pustulata, C. rupicola), four of them strictly endemic to a single massif.
    10. 10Canephora as the future, and its limitsCanephora today accounts for about 40% of world production, against 25% in the early 1990s.
    11. 11What remains to be saved: 60% of species threatenedWild arabica itself is classed as “endangered”, and how it got there is the most troubling fact in the article: assessed on the usual criteria, it comes out as “least concern”; once climate projections are built in, it jumps three categories.
    12. 12Gene banks: a plantation, not a vaultThe coffee seed does not accept the treatment that makes large seed reserves possible.
    13. 13Economics: record output, tiny farms, underfunded researchThe paradox of 2025-2026 comes down to two figures.
    14. 14Regulation: the European deforestation regulationFor coffee, the whole difficulty comes down to one verb: geolocate.
    15. 15Demand: Asia, specialty coffee, coffee without the beanDemand is shifting east. The USDA's January 2026 GAIN report puts the Chinese coffee market at 42 billion dollars in 2024.
    16. 16What we still do not knowThe review by Yang and coauthors (2026) lists explicitly what science does not know: the function of candidate genes in a tetraploid background, the biosynthetic pathways of…
    17. 17Today (September 2026)Where do things stand as this plate closes?

    Elsewhere on the site, the passages that deal with the same things as this page. Computed from the text, not picked by hand.

    DiseasesToday: 2023-2026Both mention Marsellesa, Starmaya and embryogenesis.CanephoraThe Timor Hybrid: what canephora gives arabicaBoth mention genome, chromosome and Timor.DiseasesThe great rust of 2008-2013, country by countryBoth mention races, rust and prices.The processesWhere the microorganisms of the tank come fromBoth mention mycorrhizae, Costa and fermentation.CanephoraKouilou, Niaouli, Conilon: the Guinean and Atlantic lineageBoth mention conilon, Congo and clones.DiseasesAnthracnose of the berries, Kenya 1922 and 1971Both mention Sudan, Rume and Batian.
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