The common sunflower belongs to the genus Helianthus.
Helianthus is a genus in the daisy family, Asteraceae. Its best-known species is Helianthus annuus, the common sunflower, which is cultivated for edible seeds, cooking oil, bird feed, and ornamental use. The name comes from Greek words meaning “sun” and “flower.”
Young sunflower heads can show heliotropism: they track the sun from east to west during the day and return eastward overnight. Mature heads usually face east rather than continuing to move. This behavior is often confused with all sunflowers constantly turning toward the sun, which is not generally true of mature plants.
Helianthus includes many perennial species native mainly to North America. Jerusalem artichoke, or Helianthus tuberosus, is another economically important member; despite its name, it is neither a true artichoke nor from Jerusalem.