The flower head is a large disc reaching 10–30 cm (4–12 in) in diameter which is made up of 16–30 individual florets which are yellow-gold in color. The outer florets are sterile and produce the outer petals of the flower head, while the inner florets will mature into the seeds in the central disc. Sunflowers are annual plants, harvested after one growing season and can reach 1–3.5 m (3.3–11.5 ft) in height. Sunflower may also be referred to as girasole and originates from North America