The hairy onion usually produces 6-14 onion heads, which are round in shape and smaller in size. Onions are usually single, purple in color, ellipsoidal in shape, and larger in size. Hairy onions are better suited to growing on black soil, while onions are better suited to growing in fertile, loose, well aerated neutral loam. Onion is a traditional high-yield crop in Northeast China, and the origin of onion is Iran and Afghanistan in southwest Asia.