Goldenrod was designated the official state flower of Kentucky in 1926. About thirty varieties of goldenrod are found in Kentucky and it grows throughout the state. Although the statute does not specify a particular variety of goldenrod, Kentucky legislature's website does (Solidago gigantea). Nebraska also adopted goldenrod as the state flower; South Carolina recognizes goldenrod as the state wildflower symbol, and Delaware designates sweet goldenrod (Solidago odora) as the official state herb.

More Info: statesymbolsusa.org