Nutrition, Sources of Potassium Nutrition Sources of Potassium Catfish, Lean Pork, Lean Veal, Cod, Flounder, Trout. Milk, Yogurt. Apricots, Peaches, Bananas, Prunes and Prune Juice, Orange Juice Dry Peas and Beans, Green Beans, Lima Beans, Stewed Tomatoes, Spinach, Plantain, Sweet Potatoes, Pumpkins, Potatoes, Winter Squash.