When a Chiba Prefectural Agriculture Experiment Station conducted a test of his soil, the report came back showing it was nutrient poor. “I could not have been more pleased,” says Asano surprisingly. “That means I haven’t added anything unnecessary.” Herein lies at least one secret to his craft.
While most farmers worry about feeding their soil with nutrients (which often means chemical fertilizers), Asano focuses on achieving a “mineral balance,” as he explains it. To do this, he uses crushed oyster shells and a sprinkling of deep-sea water from off the coast of Mie Prefecture, which he keeps at a constant 3 degrees Celsius (the same temperature of the water when it was collected). The shells and the seawater are both rich in minerals, especially sodium, magnesium and calcium, giving the soil what he sees as a “primal quality.”
“Life came from the sea,” he tells me, “so what better place to get the basic ingredients for my soil.” He also does his best to leave the vegetables alone, in what he likes to call “untended farming.”