Three subspecies occur in Florida.  The subspecies ranges somewhat overlap.  Subspecies cruiseana is listed as Endangered by the State of Florida. In , Tolerance, Not salt tolerant of inundation by salty or brackish water. High. Can tolerate significant and ongoing amounts of salty wind and salt spray without i , Considertions, Becomes less than attractive after flowering. , Wildlife, Primarily wind dispersed, but small birds consume seed. , Habitat, Scrub, sandhills. , Did You Know?, Showy flowers Butterflies and bees including green metallic, sweat, leafcutter, bumble and mining bees (Florida Wildflower Foundation).

The genus name honors the English botanist William Vernon, who did fieldwork in North America. Back of a moist wildflower garden. Can also use on the , Tolerance, Not salt tolerant of inundation by salty or brackish water. Some tolerance to salty wind but not direct salt spray. , Habitat, Exposed sand and gravel bars of streams during low water, stream banks, hydric to wet mesic pine flatwoods. Rich soils. Ruderal. , Did You Know?, Showy flowers Nectar attracts butterflies and native beens.  Larval host for spring azure butterfly.