Just about two weeks ago, I got married! We had sunflowers for the ceremony, and they were lovely. A few days later, we here at IALF attended the National Agriculture in the Classroom Conference in Kansas City. Though we primarily stayed on the Missouri side, Kansas’s state flower is the sunflower. So I got to thinking about this plant. I knew there are many uses, but are all sunflowers the same? Let’s find out!
Sunflowers are a beautiful addition to a bright bouquet, but that isn’t their only purpose. We also grow sunflowers as an oil crop, and as a “confectionary” crop for human consumption! There are about 70 species of sunflowers, and they all share the genus Helianthus. The common sunflower, Helianthus annuus, has many cultivars that produce slightly different variations of the same species of flower.
The two major agronomic uses for sunflowers are as an oilseed crop and as a confection crop. You can tell the difference between these two types of sunflowers by their seeds. Confection sunflower seeds, like the kind we eat, have white stripes on them. Oilseed sunflower seeds are all black, and are generally smaller.
To further distinguish the sunflowers, oilseed sunflowers can be split in three different categories: linoleic, mid-oleic (also called by the brand name NuSun®), and high oleic. This basically just refers to the chemical makeup of the lipids in the seed. Linoleic sunflower oil is polyunsaturated, mid-oleic sunflower oil has low saturated fat levels, and high oleic sunflower oil is mostly unsaturated and is trans-fat free.
According to one sunflower farmer from California, oilseed sunflower seeds are the preferred type when making bird seed mixes. However, some kinds of confection sunflower seeds can also be used.
Commercial oilseed varieties can be purchased based on oleic content, disease resistance, and higher yield. Most commercial varieties are hybrids, so sunflower seed farmers would buy seeds every year.
Most oil-type sunflower seed is processed in North Dakota and western Kansas. With the remaining seed material, a sunflower seed meal is made and can be used as livestock feed.
In contrast, confection variety sunflowers only take up about 10-20% of the crop each year, according to the Thomas Jefferson Agricultural Institute. These seeds fetch a premium at market, but also can be a trickier crop to cultivate and sell. Farms looking to grow confection sunflower seeds need to be close to a processing facility for the seeds. They also need to be mindful of pests and high winds, which can damage the large seed heads of these varieties more easily than those of oilseed sunflowers. Though these sunflowers may have a higher risk, the higher reward of premium prices may pay off for some producers.
You may know from personal experience that sunflowers sold for human consumption can come either in the hull, or dehulled. What happens to the hulls of those that are marketed without? Well, most of them are used as turkey bedding! The rest are ground into pellets that can serve as a supplemental fiber source in animal feed.
Commercially grown sunflowers for oil or confection use are harvested much later than the sunflowers in the flower shop. The petals have dried up, and the center of the flower is packed with seeds. Farmers use combines with a corn header to harvest them. Though sunflowers are primarily grown in the upper Midwest due to a short growing season, they are also very drought tolerant, so you may see them as far south as Texas! Here’s a great video from a Texas news station that learned more about the crop.
Not counting seed producers (farmers raising sunflowers to be harvested as next year’s seed crop), the last kind of sunflower production is for the ornamental uses we all enjoy. The different varieties can range from large flowers great for bouquets or small flowers better for boutonnieres. Many of these types of sunflowers are also hybrids!
In summary, sunflowers are an interesting, versatile, hardy, useful, beautiful plant and crop. Though we may call them weeds here in Iowa, our neighboring states find them to be an important part of their agricultural industry. Maybe we can learn more from this plant in the future!