People tend to prefer the white part of the scallion for reasons of taste, and often discard much of the tougher green stem. In response to market demand, farmers pile up earth around the developing scallions to make them grow whiter and taller.
為了應付市場的需求，蔥農隨著蔥株成長，得培土二、三次，把蔥白埋在深土裡，才能既白且長；蔥販賣蔥時，也往往先去掉大半的綠葉。