A finch can eat a wide variety of fruits and vegetables. However, fruit and vegetables should only make up about 25 percent of a finch's diet. A finch needs the nutrients found in nuts, seeds and birdseed. They also require supplements to live a long and healthy life. However, as long as the finch receives about 75 percent of its basic nutrition from seeds and nuts, it is fine to give the finch nearly any kind of fruit or vegetable. Remember to buy organic fruit and vegetables, when possible. The chemicals used to kill pests in non-organic food---while harmless to humans---can lead to health problems or death in a small bird. Also, be sure to choose brightly colored fruits or vegetables, when possible, to catch your finch's eye.
Leafy greens are some of the best vegetables to feed to your finch. Always feed fresh vegetables rather than frozen. You also can give your finch leftover or slightly browned lettuce from the fridge, which is no longer suitable for human consumption. Romaine lettuce, spinach, parsley, cilantro, mustard greens, dandelions, collard greens and spring mix are all appropriate greens to feed a finch, on a somewhat regular basis.
Finches can eat almost any vegetable. For hard vegetables, such as sweet potatoes and squash, grate the vegetables---as you would grate cheese---for easier consumption. Finches can eat squash, zucchini, beets, tomatoes, corn, bell peppers, carrots, broccoli and nearly any other fresh vegetable.
Finches can eat a wide variety of fruits, as well. The only type fruit you should stay away from is citrus, as citrus fruits may cause the bird to choke. Feed your finch apples, pears, pumpkins, mangoes, papaya, peaches, grapes, honeydew melons, and nectarines. Always cut the fruit into edible pieces and only feed the finch minute amounts at a time, to prevent overeating.