Pineapples that will one day become pizza toppings or sweeten morning smoothies for Americans begin life here. They grow in Thailand’s sandy loam, tended by farmhands wearing industrial rubber gloves, lest they nick themselves on the fruit’s bladed leaves. Once harvested, they’re exported to the United States, which typically consumes more canned pineapple from Thailand than from any other country. On a recent April morning, farmers walk these rows tossing ample handfuls of tiny white pellets called urea – the world’s most widely used chemical fertilizer. Each pellet is packed with nitrogen, which boosts photosynthesis to make plants grow bigger and faster. But the Southeast Asian croplands that feed the world now face a fertilizer crisis. Urea has become expensive and harder to find. Why We Wrote This American consumers buy many agricultural products from Southeast Asia, where farmers are dealing with a fertilizer shortage because of the Iran war.…