Ok, stop snickering. A pot herb is one that is made edible by cooking in water in a pot, such as spinach, collards, turnip greens,Swiss chard, plantain, or lamb's quarters. Most of these can also be stir-fried, or cooked in bacon grease, and served with (non-sweet) corn bread.

Picking greens is a high art in some parts of America, since the best pot herbs aren't cultivated, but "found" in ditches and fields. FWIW, I'm a New Englander, but learned how from an old great-aunt, who was one of the last indentured servants freed in America, when an amnesty was declared during the First World War.

Ah, the pleasures of poverty...no lie.