They can reach heights of 14 feet, but it’s the blooms that are the most impressive. These sunflower heads can get enormous!! With the characteristic bright and sunny yellow petals of their cousins. Mongolian Giant sunflowers have a single giant bloom at the top with large green leaves all the way down. Think Jack and the Beanstalk, but with a gorgeous sunflower at the top! The stalks of these flowers are extremely thick and woody to help support the height and weight of the bloom. At the center of the bloom are tons of large, edible seeds, usually as long as an inch and a half. That makes these seeds the longest of any sunflower variety and the perfect snack when roasted!