Helianthus

Helianthus or sunflowers is a genus of plants comprising about 70 species in the family Asteraceae. The genus is one of many in the Asteraceae that are known as sunflowers. Except for three species in South America, all Helianthus species are native to North America.

Description

The common name, "sunflower", typically refers to the popular annual species Helianthus annuus, or the common sunflower, whose round flower heads in combination with the ligules look like the sun. This and other species, notably Helianthus argophyllus (silverleaf sunflower), are often used in gardening and landscape design projects.

Uses

Sunflowers are cultivated for their edible seeds, which are an important source of oil for cooking and margarine. The seeds are also used in bird feeders, and the flowers can be used for decorative purposes.

Cultivation

Sunflowers thrive in full sun and prefer long, hot summers. They are remarkably tough and will grow in any kind of soil as long as it is not waterlogged.

Species

There are many species of sunflowers, including Helianthus annuus, Helianthus argophyllus, Helianthus petiolaris, and Helianthus tuberosus.

See also

• List of Helianthus species
• Sunflower oil
• Sunflower seed

References

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  Sunflower sky backdrop
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  Sunflower disk
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  I-40W Sunflowers
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  A sunflower seed growing
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  Helianthus whorl
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  Sunflower Face
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  Sunflower Kamand DSC 2856
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  Helianthus decapetalus 'Plenus'
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  Helianthus petiolaris
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  Helianthus giganteus
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  Helianthus Tuberosus
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  Helianthus x laetiflorus