Common Sunflower (Helianthus annuus L.)

↑Range - Expand

Legend	Color
Native
Expanded
Native or Not Present
Native or Expanded
Expanded or Not Present

This tentative map is based on our own research. It may have limited data on Canada and/or Mexico, and there is some subjectivity in our assignment of plants as introduced vs. expanded. Read more in this blog post.

The exact native range of this species is not known, but it is widely agreed to be native to western North America, and to have expanded eastward. Native Americans probably brought it eastward somewhat, through using it as a food source, and then it expanded even more after European colonization. It thrives in active and abandoned cropland, roadsides and railroads, pastures, waste ground and construction sites. We mark the entire new range Expanded because it is largely connected and contiguous with the native range, separated only by small gaps of a few counties, even in the sparser parts of its range.