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Otherwise known as the helianthus annuus, the sunflower is an annual plant that is native to the Americas. Domesticated for food production over 3000 years ago, this state flower of Kansas derives its name from its oversized flowerhead which looks like the sun.
Brought to Europe in the 16th century by early European explorers, the sunflower fast became a much-used ingredient in cooking. Today, it is an important crop with leaves being used as cattle feed, fibrous stems being used for paper production and sunflower oil, which is extracted from the sunflower seeds, also used in biodiesel.
There are 82 species in the sunflower genus, each of them native to North America and each of them characterized by their large flowerheads. Within each sunflower flower lies between 1,000 and 2,000 individual florets or miniature flowers that are clustered together in an interconnecting spiral pattern. It is these small flowers that eventually mature into the sunflower seeds that are crushed for oil. The sunflower is also characterized by its ability to grow high, with sunflowers averaging between five and twelve feet in height.
Young sunflowers demonstrate heliotropism (phototropism) or sun tracking, and change orientation during the day to follow the sun’s course from east to west. When the sunflower matures and stems and leaves stop growing, it stops exhibiting phototropism and remains in place. Thanks to its drought resistance and disease resistance, over the centuries, the wild sunflower has been crossed with many other types of plants. 38 species of sunflower are perennial and grow from deep, persistent roots and have large tubers in which nutrients can be stored. By consistently breeding wild sunflowers with large tubers, it is now known that Native Americans created the Jerusalem artichoke.
For most successful cultivation, sunflowers should be grown in full sun and in moist, well-drained soil. Sunflowers require at least six hours of sun a day and should be watered daily. For commercial crop planting, seeds are planted around a foot and a half apart and an inch deep. In recent years cut sunflowers have become popular flowers for domestic enjoyment. Cut sunflowers are harvested when the blooms are almost completely open.
To order Sunflowers, check out ProFlowers Sunflower bouquets.
(Images provided by AFIF)