Many foodies pin the blame for farming’s ills on “unnatural” industrial agriculture. Agribusinesses create monocultures that destroy habitat and eliminate historic varieties. Farmers douse their crops with fertiliser and insecticide, which poison streams and rivers—and possibly human beings. Intensive farms soak up scarce water and fly their produce around the world in aeroplanes that spew out carbon dioxide. The answer, foodies say, is to go back to a better, gentler age, when farmers worked with nature and did not try to dominate it.

However, for those who fancy some purple-ruffles basil and mizuna with their lamb’s leaf lettuce, there is an alternative to nostalgia. And it involves more intensive agriculture, not less... [+]