For the first time ever, farmers the world over — all at the same time — are testing the limits of how little chemical fertilizer they can apply without devastating their yields come harvest time. Early predictions are bleak.
In Brazil, the world’s biggest soybean producer, a 20% cut in potash use could bring a 14% drop in yields, according to industry consultancy MB Agro. In Costa Rica, a coffee cooperative representing 1,200 small producers sees output falling as much as 15% next year if the farmers miss even one-third of normal application. In West Africa, falling fertilizer use will shrink this year’s rice and corn harvest by a third, according to the International Fertilizer Development Center, a food security non-profit group.