The morning light washes over Norbu Gyeltshen's terraced fields with a soft, deliberate glow, catching the pale seed heads of quinoa that rise among the maize and chili. When Norbu and his wife, Pema Sedon, first planted the crop in their little town of Bartsham in eastern Bhutan, it was little more than an experiment: one row among many in the red soil that had only ever held rice and buckwheat.

Now the crop stands at the centre of their work. Last season they harvested about 1 200 kilograms, enough to see the difference in both income and ease. The increased production could be because of the different variety and the use of organic manure, Norbu says, brushing the soil from his palms.