When cooking ginger soup, choose old ginger, because the ginger pieces of old ginger are shiny, fully expanded and ripe, with solid and tight meat, more fiber and strong spicy taste. Choose fresh ginger with bright colors, soft swelling and no cracks and blackening on the epidermis, and don't choose ginger with wrinkles and dry hair.

Ginger is native to the tropical region of Southeast Asia. It likes warm and humid climate, and its cold resistance and drought resistance are weak. The plants can only grow in frost-free period. The optimum temperature for growth is 25-28℃. When the temperature is lower than 20℃, it will germinate slowly, and the plants will wither in case of frost, and the roots will lose their germination ability completely.