Robusta

Robusta is the hardier, higher-caffeine coffee species grown at lower altitudes, used heavily in instant coffee and blends, and traded on its own futures contract.

Robusta coffee trees tolerate lower elevations, warmer temperatures, and harsher growing conditions than arabica, and they yield more beans per tree with a higher caffeine content, though most tasters find the resulting cup harsher and more bitter. Vietnam and Brazil are the largest robusta producers.

Because it is cheaper to grow and more resistant to some diseases, robusta trades at a discount to arabica and dominates instant coffee and many commercial blends, where cost matters more than cup quality. It trades on its own futures contract, separate from arabica, and the differential between the two species’ prices shifts with relative harvest conditions in their very different growing regions. A weak arabica harvest can push blenders and instant coffee makers to lean more heavily on robusta, tightening that market too.