A well-known sunflower characteristic is that the flowering heads track the sun's movement, a phenomenon known as heliotropism. Most newer varieties have heads that will droop to face the ground as the plants mature. This has the potential of reducing bird damage and reducing some disease development that could occur if water collected in the seed head. Sunflower plan heights vary widely, but most full-season field crop varieties range from 5 to 7 feet tall, except for dwarf varieties, which are more typically 3 to 4 feet tall with smaller grain heads. Stems normally are unbranched, with a single seed head on each plant.
Vegetable oil is the main market for sunflower in the U.S. and worldwide.
Sunflower oil generally is considered a premium oil due to its light color, mild flavor, low level of saturated fats and ability to withstand high cooking temperatures. Despite these advantages, it is normally handled in the U.S. marketplace as a commodity vegetable oil. In the U.S., sunflower is perhaps better known as a snack food, even though that is actually a smaller market for the crop. Another well-known use of sunflower in the U.S. is as a birdseed, most typically mixed with millet and other grains. The black oilseed varieties usually are favored over the striped confectionary seeds, since they cost less per pound.