Sunflowers (Helianthus annuus) are large, iconic flowering plants known for their tall, hairy stems and big flower heads that look like the sun, featuring bright yellow "petals" (ray florets) surrounding a dark central disk of tiny, tightly packed flowers (disk florets) that become seeds. They grow from 3 to 15 feet tall, have broad, rough leaves, and are cultivated globally for oil, snacks (seeds), and ornamental use, with mature heads famously facing east.