In the wild, finches eat a varied diet of seeds, leaves, fruits and shoots. Some varieties of finches also eat spiders, insects and worms. This dietary variation provides them with the wide array of nutrients that they need for good health.
Many people who keep finches in captivity assume that they can thrive eating only seeds. Although the birds may survive on this diet, it is not ideal. Providing a variety of foods, such as those that would be available to a wild finch, enhances their health. Fruits and vegetables that finches love include apples, collard greens, pumpkin, spinach and tomatoes. They should not be fed large amounts of iceberg lettuce, since it is not very nutrient-dense, and avocados should be avoided since they contain a toxin that can kill finches. Frozen vegetables can be fed to finches when fresh ones are not available.
Finches in captivity can also be fed live foods, including mealworms and wax worms. They should also be provided with a seed-based food made specifically for finches. Birdseed mixes for finches contain smaller seeds than those made for other birds. Finch owners should make sure seeds are fresh before feeding them to their birds, as seeds can turn rancid. If seeds sprout after being folded into a wet paper towel for several days, they are fresh and safe to feed.