http://en.wikipedia.org/wiki/C... It is a long description but see if this helps.
The Cultivar name is what the plant is first registered under , And the Trade name is a nicer name for marketing.
EXAMPLE - Cultivar Heuchera Tnheu 043 = Trade name Heuchera Dolce Peach Melba
Cultivar Echinacea Emily Saul = Echinacea After Midnight
