On May 28, 1767 Jefferson observed "Snap-dragon" blooming at Shadwell, his childhood home &, four years later, he listed this native of southern Europe among the hardy flowers to be naturalized in a "shrubbery" at Monticello. Jefferson's reference is the earliest known mention of this plant in an American source. The Snapdragons at Monticello came in 1985 through our friendship with the curator of gardens at Hatfield House, a 16C country estate outside London, where the species is naturalized in the landscape.
Research & images & much more is available directly from the Monticello website - to begin exploring, just click Monticello.org.