Native Americans domesticated the sunflower, a native of the Great Plains. They used the seed for food, extracted oil from them for paints, and used bloom petals for dye. The wild form, Helianthus annuus L., is still common throughout the Great Plains in cultivated fields, pastures, gardens, roadsides, and other disturbed sites. The plants provide cover, and the seeds furnish energy and protein for a wide range of wildlife species, but they are considered weeds because they compete with cultivated crops.
Cultivated sunflowers are grown as either an ornamental plant in the landscape or as an agronomic crop used for its edible seed or extractable oil. Ornamental sunflowers have been developed to produce blooms of magenta, white, and orange and to reach heights of one to fifteen feet. They are commonly used in the back of garden beds for height, color, and texture, or as screens and alongside fences. Kansas, the Sunflower State, has adopted it as its state flower.
Agronomic sunflower production is divided into two market classes, oil and confectionery. Most of the acreage in the Great Plains is planted with the oil type. The oil is used primarily in cooking and baking. Confectionary types are grown for the edible roasted seed. Acreage in confectionary sunflowers is contracted with processing companies and is subject to strict guidelines. Confectionery seeds not meeting the guidelines go into birdseed markets. Recently, a third market class has developed based on specialty cooking oil markets.
Sunflowers in the Great Plains are grown under both irrigation and dryland-farming methods but mainly under dryland farming. Yields under irrigation are typically double those of dryland. Although sunflowers are cultivated in significant amounts in western Kansas and Nebraska, eastern Colorado, and parts of the Texas Panhandle, U.S. production is dominated by South Dakota and, especially, North Dakota. In Canada, fully 90 percent of national production comes from central Manitoba.
Sunflowers work well in rotation with winter wheat, as a wheat-fallow-sunflower rotation. In this system two crops are harvested in a three-year period. They are sown in May and harvested in late September or October. Sunflowers should be planted into a firm seedbed when soil temperatures are above 50ºF. They grow best on medium-textured soils, such as loams. Planting is done with a row crop planter equipped with special plates or with a grain drill. Seeding rates are 14,000 to 21,000 plants per acre under dryland conditions and 20,000 to 25,000 plants per acre under irrigation. Sunflowers are harvested with the use of a combine with special extensions (sunflower pans) in front of the cutter bar.
The sunflower, being native to the region, is vulnerable to a wide array of insects and diseases that can cause serious economic yield reductions. Common insect pests are the sunflower seed weevil, sunflower moth, grasshoppers, and the sunflower head clipper weevil. Common diseases are stalk and head rot, rust, Phoma black stem, and downy mildew.
See also INDUSTRY: Oilseeds
James Schild University of Nebraska-Lincoln
Schild, Jim, Dave Baltensperger, Drew Lyon, Gary Hein, and Eric Kerr. "Sunflower Production in Nebraska." G91– 1026, University of Nebraska, 1991.
McMullen, Marcia P. "Sunflower Production and Pest Management." Extension Bulletin 25. North Dakota State University, 1985.