The sunflowers scientific name is helianthus. The name comes from two words, Helios meaning sun, and Anthos, meaning flower. The sunflower often follows the sun, and this characteristic is how the flower got its name. The sunflower is not one flower, but a cluster of more than 2000 tiny flowers growing together. A sunflower�s head can grow to be as big as 2 feet across and the plant itself can be as tall as 18 feet. The tallest sunflower grown on record was 25 feet tall in the Netherlands.