Sunflower Production In South Dakota

Ruth Beck
Agronomy Field Specialist

Above: Field of Sunflowers in central South Dakota, 2013Photo credit: Ruth Beck

In 2013 South Dakotans planted 617,000 acres of sunflowers. No other state came close to this number of acres. North Dakota was second, planting just under 500,000 acres of sunflowers in 2013.

There are two types of sunflowers planted in South Dakota; oilseed types used for birdseed or crushed to make sunflower oil and confection types or those grown for human food markets. Seeds of the two types are easily differentiated. The oilseed type has small black seed and a thin hull or shell that adheres to the kernel. The confection or nonoil seed types have a thicker, larger, hull and a larger seed that is easily separated from the hull. The shells are usually a lighter shade and have some white striping. Typically the confection plants produce seed that has lower oil percentage and test weight. Oilseed types are the most popular in South Dakota, being grown on about 86% of acres in 2013. They average around 42% oil content and are marketed into the oil and the birdseed markets.

As with any crop, variety selection is a very important part of production. Sunflower varieties are hybrids and are therefore purchased each year from commercial seed companies. Hybrid selection should reflect desirable yields; high oil percentage for oil types, proper maturity, proper seed size for confection types, insect tolerance, and disease resistance. Standability and head position after flowering are also selection criteria. Most seed is treated with a fungicide and insecticide to protect the germinating seedling. Sunflower varieties are tested annually in SD. Results are posted in the iGrow Sunflower and Flax Variety Trial Results article.

Although sunflowers are classified as intermediate in water use efficiency (yield/inch of water), they are often considered drought tolerant because they have a deep tap root. This allows them to extract water from deep in the soil profile and also enables them to use nitrogen and other nutrients that leach below the root zone of shallow-rooted crops. Careful consideration should be given to the type of crop that follows sunflowers, in part, because their ability to scavenge water and nutrients can affect following crops.

Sunflowers are produced primarily in the central and western region of South Dakota under no till crop production systems. No till systems rely heavily on diverse crop rotations. Sunflowers should be planted in a diverse rotation in order to minimize issues with disease, weeds and insects. Since sunflowers are native to this area, risks from diseases are magnified by short sequencing of sunflowers in a crop rotation.