Remove and discard stems and discolored spots from greens. Wash greens thoroughly; drain and tear greens into pieces. Set aside.
Slice salt pork at 1/4-inch intervals, cutting to, but not through, the skin.
Combine salt pork, 3 quarts water, pepper, and, if desired, sugar in a Dutch oven; bring mixture to a boil. Cover, reduce heat, and simmer 1 hour.
Add greens, and cook, uncovered, 30 to 35 minutes or until tender. Serve with a slotted spoon.