Helianthus

Helianthus is a genus comprising around 50 species of annual and perennial flowering plants in the daisy family Asteraceae, commonly known as sunflowers, native to North America. Sunflowers are typically tall plants that can reach 300 centimeters or more in height, with each flower head made of tiny florets arranged in a disc structure, yellow ray florets on the exterior and yellow or maroon disc florets inside, and leaves that are dentate and often sticky. The most familiar member is the common sunflower, Helianthus annuus, which grows during summer and early fall and serves as the national flower of Ukraine; another economically important species is the Jerusalem artichoke, Helianthus tuberosus, valued for its edible tubers, while some perennial species such as the whorled sunflower are endangered.