In early winter, leeks are dug out from underground roots. Choose thick roots and squeeze them on a specific square bed. According to the needs of growth, keep the temperature and humidity of the environment above 20 degrees in a semi-cloudy and semi-sunny greenhouse and let it grow. Because this kind of leek gets virtual light instead of direct sunlight, the upper part of the stem and leaf is light green and the lower part is yellow. Therefore, it is called yellow leek or yellow leek.

Before 1980s, there were no greenhouses, and farmers planted leeks indoors, using horse manure as heating material and fertilizer. The heating of horse manure can make the soil temperature reach 25 degrees, and there are a lot of leeks to be cultivated in a room. Heating materials alone can turn this room into a greenhouse, and the temperature can reach above 20 degrees.