Helianthus annuus

Helianthus annuus is a wide-ranging annual herb found in open habitats. It occurs natively in the Great Plains of North America, from Manitoba and Saskatchewan, Canada, and Washington east to Minnesota south to Texas and California in the United States, and south to Mexico. It is commonly cultivated and naturalizing or introduced throughout much of Canada and the eastern United States. There are over 1000 occurrences, which potentially face threats from development, rights-of-way maintenance, invasive species, and other threats in some places. Little is known about trends, but with a large range extent and large number of occurrences, abundant habitat, and broad habitat preferences, this species is considered secure.

Helianthus annuus occurs natively in the Great Plains of North America, from Manitoba and Saskatchewan, Canada, and Washington east to Minnesota south to Texas and California in the United States, and south to Mexico. It is commonly cultivated and naturalizing or introduced throughout much of Canada and the eastern United States (FNA 2006, Brouillet et al. 2025, Weakley and the Southeastern Flora Team 2025). The native range extent was estimated to be over 8 million square kilometers using herbarium specimens and photo-based observations documented between 1994 and 2025 (GBIF 2025, iNaturalist 2025, RARECAT 2025, SEINet 2025).

By applying a 1 km separation distance to herbarium specimens and photo-based observations documented between 1994 and 2025, it is estimated that there are over 1000 occurrences rangewide (GBIF 2025, iNaturalist 2025, RARECAT 2025, SEINet 2025). This species is occasionally cultivated (FNA 2006), and observations were not evaluated for evidence of cultivation, though observations outside the native range were excluded.

Although threats are not widely documented, this species is potentially threatened by development, rights-of-way maintenance, invasive species, and other threats in some places. However, their overall impact is likely negligible given the species' broad range and large number of occurrences.