A: They are the fruits of the potato plant. Some people call them "potato berries" or potato fruits. They look like tomatoes, but are NOT edible. Potatoes and tomatoes are both from the nightshade family. The potatoes produced from these seeds will not have the same characteristics than the plants they came from hence the reason farmers start with tubers and not seed. According to Iowa State University IPM News, "The potato fruit are of no value to the gardener. Potato fruit, as well as the plant itself, contain relatively large amounts of solanine. Solanine is a poisonous alkaloid. The small fruit should NOT be eaten. Since potatoes don't come true from seed, no effort should be made to save the seed."