Sweet goldenrod (Solidago odora) was designated as the official state herb of Delaware in 1996. An aromatic, anise-flavored tea can be made from the dried leaves and dried fully expanded flowers, and the blossoms are also used as a flavoring in cooking. The tea made from sweet goldenrod has medicinal properties and is useful in the treatment of coughs and colds, among other ailments. The root can be chewed to treat a sore mouth.

Growing up to six feet tall, sweet goldenrod is indigenous to Delaware (and much of the eastern U.S.) and is widespread throughout the state (commonly found in Delaware's coastal areas and along the edges of marshes and thickets). Sweet goldenrod is considered threatened in Ohio, Vermont, and New Hampshire.

Source:

Delaware State Plants: Delaware Official Website
Plants For A Future - Solidago odora: ibiblio Library

Links:

American Food and Agricultural Symbols
American Food Holidays