THE BLANKETS IN THE COMPOST PILE

ON A CAROLINA summer afternoon too hot for much else but lies and iced tea, Ken and I sat in the shade beside the Urban Ministry Community Garden for the homeless - talking compost.

Ken was a big man, over 6 feet and 200 pounds, with a silver gray ponytail, a scraggly beard and a wry, scrunchy smile. He had the aura of a saint, disguised as a homeless man in old tattered clothes, a roll-your-own cigarette protruding from his lips. Before ending up on the streets, Ken had grown a garden at his suburban house in Michigan. Decades later, he was still proud of it: "100 percent organic, all kinds of bulbs and shrubs and roses. For my wife."

In the heat, our compost discussion …