Apium graveolens is a plant species in the family Apiaceae commonly known as celery (var. dulce) or celeriac (var. rapaceum), depending on whether the petioles (stalks) or roots are eaten: celery refers to the former and celeriac to the latter. Apium graveolens grows to 1 m tall. The leaves are pinnate to bipinnate leaves with rhombic leaflets 3–6 cm long and 2–4 cm broad. The flowers are creamy-white, 2–3 mm diameter, produced in dense compound umbels. The seeds are broad ovoid to globose, 1.5–2 mm long and wide.
Apium graveolens is used around the world as a vegetable, either for the crisp petiole (leaf stalk) or the fleshy top root.
In temperate countries, celery is also grown for its seeds. Actually very small fruit, these “seeds” yield a valuable volatile oil used in the perfume and pharmaceutical industries. They also contain an organic compound called apiol. Celery seeds can be used as flavouring or spice, either as whole seeds or ground and mixed with salt, as celery salt. Celery salt can also be made from an extract of the roots. Celery salt is used as a seasoning, in cocktails (notably to enhance the flavor of Bloody Mary cocktails), on the Chicago-style hot dog, and in Old Bay Seasoning.
Celery, onions, and bell peppers are the holy trinity of Louisiana Creole and Cajun cuisine. Celery, onions, and carrots make up the French mirepoix, often used as a base for sauces and soups. Celery is a staple in many soups, such as chicken noodle soup