Definition that contains biennia
- beet biennial Eurasian plant usually having a swollen edible root; widely cultivated as a food crop
- blazing star biennial of southwestern United States having white stems and toothed leaves that is grown for its large pale yellow flowers that open in early morning
- red bird's eye biennial European catchfly having red or pink flowers; sometimes placed in genus Lychnis
- common beet biennial Eurasian plant usually having a swollen edible root; widely cultivated as a food crop
- western wall flower biennial or short-lived perennial prairie rocket having orange-yellow flowers; western North America to Minnesota and Kansas; sometimes placed in genus Cheiranthus
- white sweet clover biennial plant; valuable honey plant
- genus hesperis biennial or perennial erect herbs having nocturnally fragrant flowers
- scotch thistle biennial Eurasian white hairy thistle having pale purple flowers; naturalized in North America
- cynoglossum amabile biennial east Asian herb grown for its usually bright blue flowers
- wild parsnip biennial weed in Europe and America having large pinnate leaves and yellow flowers and a bitter and somewhat poisonous root; the ancestor of cultivated parsnip