Skip to main content
You are here
Facebook icon
Pinterest icon
Twitter icon

Helianthus annuus (sunflower)

Sunflower is a beautiful and nutritious plant widely cultivated for its edible seeds and oil.
Helianthus annuus, sunflower

Sunflower (Photo: George Shephard)

Species information

Scientific name: 

Helianthus annuus L.

Common name: 

Sunflower (English); tournesol (French); girassol (Portuguese); alizeti (Swahili)

Conservation status: 

Widespread in cultivation, rarely naturalizing.

Habitat: 

Cultivated in relatively cool temperate to warm subtropical climates. More information below.

Key Uses: 

Oil, food, livestock feed, biofuel.

Taxonomy

Subclass: 
Superorder: 
Asteranae
Order: 
Asterales
Family: 
Compositae/Asteraceae
Genus: Helianthus

About this species

Native to North America, Helianthus annuus, better known as sunflower, is both beautiful and useful. It is widely cultivated for its edible seeds and oil and, to a lesser extent, as an ornamental. Nutritionally, the seeds contain up to 46% of polyunsaturated oil with a high percentage of linoleic acid and up to 20% protein of a high biological value. Sunflower belongs in the daisy family, Compositae (Asteraceae), and is characterised by having a flower head (capitulum) with outer yellow ray florets, which serve to attract pollinators, and inner brownish disc florets which are fertile and are arranged in spiral whorls from the centre of the head. Sunflower is pollinated by bees and some farmers place bee colonies in sunflower fields which produce honey as a by-product.

It is a common misconception that sunflower heads are heliotropic and track the sun across the sky. The alignment of sunflowers in a field is due to heliotropism at an earlier stage of their development, while the flower heads are still in bud. The buds follow the sun until the end of the bud stage when they finally position themselves facing east. This behaviour makes blooming sunflowers growing in the open like living compasses with north to the left, west behind and south to the right. 

Genus: 
Helianthus

main info

Courses at Kew

Students learn about plant taxonomy and identification

Kew offers a variety of specialist training courses in horticulture, conservation and plant science.

Why People Need Plants

image of book cover

A compelling book from Kew Publishing that explores the crucial role that plants play in the everyday lives of all of us.