Tomatoes, especially heirloom tomatoes, are known for their incredible diversity of colors, shapes, textures, sizes, and tastes. Colors can range from red to purple, to yellow and orange. There are over 5,000 types of tomatoes listed in the Seed Savers Exchange, the largest nongovernmental seedbank in the United States. Estimates show there are between 600-750 commercially available heirloom tomato varieties sold today.