History

The sunflower may be one of America’s unsung heroes. One of the few cultivated plants native to North America, it is believed that wild sunflowers covered thousands of square miles of land that is now the western United States. Sunflower remains have been found in North American archaeological sites dating from as early as 3,000 B.C. The center of origin for wild sunflowers is considered to be the Western Plains of North America, but the ancestors of the cultivated type have been traced to the Southwest or the Missouri-Mississippi River valley areas. The first breeders of sunflowers appear to be the Ozark Bluff dwellers who selected plants and seed for cultivation.

The sunflower success story really starts after its introduction in Russia. The Holy Orthodox Church of Russia forbade the use of many foods during Lent and Advent, including many which were rich in oil. The Russians eagerly accepted the sunflower recognizing it as a source of oil that could be eaten without breaking the laws of the church. Russia soon became the foremost producer of sunflower seed, a title they still hold. In the last 50 years, the Russians have bred sunflowers for high oil and improved resistance. In 1966, an open-pollinated, Russian-bred cultivar was introduced into the United States. This and other cultivars began the first sustained commercial production in the U.S. of the oil-seed type of sunflower. Since 1966 many research programs in the U.S. have improved the oil yield in sunflower hybrids. The sunflower now ranks second among all seed crops in the world as an important source of edible vegetable oil.

Cultivars

Sunflowers grown in home gardens are divided into two categories – Helianthus and edible seed types. Helianthus are grown for their decorative flowers. They come in many colors and sizes. Gardeners can choose a dwarf (15 inches high) fully double, golden chrysanthemum type, or a 4 foot pure yellow or white Helianthus with shades of primrose. The tallest Helianthus, 5 to 6 feet, provides the widest color range – yellow, gold, bronze, mahogany red, and bicolor blooms. These flowers do produce seeds if left on the plant, but they are small and probably best left for wildlife.

The most widely grown variety for edible seeds is Mammoth. First offered in the 1880s by a U.S. seed catalog, it was listed as Mammoth Russian. One of the tallest sunflowers, Mammoth is most often used to produce prize-winning seed heads. New cultivars have been introduced that are shorter (only 6 feet), earlier (68 days), and that have been bred for disease tolerance.

Culture For Large-seed Heads

The sunflower is a very vigorous growing plant, reaching 6 feet in five months. To keep up with this growth, a booster application of fertilizer is recommended when the flower head begins to appear. In some cases, the stem may need to be staked or somehow supported as the seed head becomes heavier and begins to bend to the ground. Winds also pose a threat of blowing over tall, top-heavy sunflowers.

The sunflower has few enemies; most common are the stem borer and stem maggot, rust, and powdery mildew. The stem borer and stem maggot can both be quite destructive as they burrow into the stem, killing all vegetation above the point of entry. Clean garden practices are the best prevention.

Sunflower Nutrition

Once thought of as bird food or snack food, sunflower seeds are not „junk food.” The sunflower seed, in fact, is very high in many minerals, vitamins, and essential acids. The only drawback is they are high in calories. The nutrients that are of quantity in sunflower seeds include protein, thiamine, Vitamin E, iron, phosphorous, potassium, calcium, and the essential fatty acids Linoleic acid and Oleic acid. The amount of protein in sunflower seed is 24 percent, putting them in the same protein league as beef. They are higher in iron than any other food except egg yolks and liver. The potassium levels are similar to raisins, nuts, and wheat germ, with higher calcium levels than soybeans. This great proportion of nutrients in the seeds is believed to improve cardiovascular health. Their high proportion of potassium, but low sodium content, makes the sunflower seeds act as a diuretic, which helps to lower high blood pressure. The essential Linoleic acid is necessary for growth and prostaglandin production, and tests have shown it to be beneficial in reducing levels of serum cholesterol.

The Ultimate Bird Food

With over 60 million Americans spending more than 12 billion dollars a year on birdseed, it would be safe to say that birds are welcome visitors to our yards, balconies, and patios. There is no ideal seed mix for all birds, but scientists who study the habits of birds have found that the black-striped sunflower seed is the closest to an ideal, all-purpose, songbird food. A feeder stocked with black-striped sunflower seed will attract mourning doves, nuthatches, cardinals, grosbeaks, and finches, not to mention jays, grackles, squirrels, and other mischievous critters.

Harvesting and Storage

Harvest when seeds in the center of each head are mature. The back of the head will turn greenish-yellow to yellow, and the bracts will turn brown. Cut with about a foot of stalk attached and hang the head in a warm, dry place. Cheesecloth or other netting tied around the head will prevent seeds from falling to the floor. If picked before completely dry, hang the head by the stalk in an airy, dry place, such as a well-ventilated attic. When thoroughly dry, gently rub the seeds from the head and store them in airtight containers, such as jars or well-tied bags.

(Originally published by Diane Relf, Extension Specialist, Environmental Horticulture, in The Virginia Gardener Newsletter, Volume 8, Number 8.)