Onion is a biennial or triennial plant and is one of the most common vegetables, especially in the south and south-east of Romania. The onion is native to Asia and in ancient times it was believed that onion gives power, being consumed by soldiers before going to battle. In ancient China it was considered a symbol of intelligence.

The onion has a bulb in the soil and on the surface of the soil the leaves are cylindrical in shape. In the second year grows the stem on top of which there is a round inflorescence that contains numerous white flowers, of small size.

For medicinal purposes, bulbs harvested at the end of the summer are used.

Onions have antimicrobial, antiinfective, antihelminitic, antibacterial, antiseptic, carminative, diuretic, expectorant, febrifuge, hypoglycemic, glandular, antithrombotic, vermifug, diuretic, hypotensive, stomachic, vasodilatory and stimulate immunity.

Onion also contains vitamin C and chrome. Chrome is a mineral that helps cells to respond to insulin and controls blood glucose levels. Green onions are rich in vitamin A.