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(Helianthus sp.) Sunflowers are so named because of their "habit" of turning their flower heads to face directly into the sun; as well as for their big, yellow flowers, which somewhat resemble a simple sun.
There are many individual species of sunflower, with the most commonly known being Helianthus annus, which produces the seeds which sunflowers are known for. All sunflower species are herbaceous annuals with a fairly rigid, sometimes hairy, stalk, alternate leaves, and prominent yellow flower heads. Wild sunflowers average two to five feet in height with flower disks up to six inches across, while cultivated varieties can be up to ten feet high and have a flower disk up to a foot across. Native sunflowers are found across the western United States from the Mississippi River to the Pacific and from northern Mexico into southern Canada. They grow in a variety of soils and habitats, and do well in dry, hot conditions and in poor soils. Blooming typically begins in early summer, and continues into early fall. All varieties have a taproot that, depending on soil type and moisture conditions, can reach a foot or more deep. Many varieties appear to have a natural immunity to insect pests.
Sunflowers were first cultivated over 3000 years ago by Native Americans, who selected plants based on the number and sizes of seeds produced. The plant was introduced into Europe, in the 16th century; while it is unknown exactly who first took sunflower plants to Europe, it was the Russians who first grew them commercially there. Russia still leads the world in commercial sunflower production, followed by Argentina, the United States, and Canada. Minnesota and the Dakotas are the leading sunflower producers in the U.S.; Manitoba is the leader in Canada.
Sunflowers are most commonly cultivated for their seeds, and one plant can easily produce several dozen seeds per flower head. Native Americans valued sunflower seeds as an easy source of nutrition and energy, and ate them raw, roasted and boiled. Natives also ground seeds into flour, which was used in breads, gravies and gruels. Sunflower seeds are still popular as snacks, as well as for their high oil content (one seed may consist of up to 40% oil). Sunflower seed oil was traditionally used as a base for medicines to treat skin rashes, chest and pulmonry ailments, colds and coughs, and even as an aphrodisiac. Modern uses for sunflower seed oil include cooking, and as a base for margarine and other food products, soaps, and lubricants. Sunflower stalks make excellent livestock fodder, and, when dried, a good fuel for cooking fires. Efforts are underway to use the fibers from green stems in the making of paper and fabrics. Sunflower hulls are used in the making of ethyl alcohol and to line plywood.
The wild native sunflower (Helianthus annus) became the official flower of Kansas in 1923.
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This page was last updated on September 23, 2017.