PURPOSE: To use an onion as a food in a state different from conventional bulb-form onion while keeping the sharp taste, sweet taste, etc., of onion and eatable in raw or various cooked forms.
CONSTITUTION: In the case of soil cultivation of onion, cultivation soil (a) composed of muck soil and cattle manure compost is put into a cultivation vessel 1 and onion bulbs (b) are embedded in the cultivation soil (a) in a relatively dense state interposing prescribed spaces. The cultivation vessel is left under dark condition (e.g. in a dark chamber) at 3-40°C and 50-85% relative humidity. The onion bulb (b) is sprouted after several days and a soft stalk and leaf vegetable (c) having a length of 45-55cm and yellow color at the upper part and white color at the lower part is grown from the sprout.