Laizhou Chinese Yam

Laizhou Chinese Yam

　　Laizhou Chinese Yam

　　As the summer heat fades and a chill gradually sets in, the best food for winter nourishment—Chinese yam—is back on the market. The streets of Laizhou and Laowan are practically Chinese yam avenues.

　　Botanically, “yam” is also known as “Dioscorea.” It is a perennial twining vine with tuberous roots that grow straight into the soil, varying in length from over a meter to just a foot. The shape is cylindrical, with a diameter of 2–4 centimeters. In early spring, propagation is done through tuber sprouts, and harvesting can be done by early winter.

　　The cultivation of Chinese yam in areas such as Laowan, Tonggui, and Shabao has a history of nearly 200 years. The yams from this region are large, uniformly round and smooth. Once peeled, the flesh is crisp, tender, and snow-white. This area consists of tidal wetlands formed by the intermingling of rivers and lakes, featuring deep soil layers with an appropriate sand content. The sandy soil is relatively sticky, fine, and loose, offering good water and nutrient retention. In rainy years, the surface dries quickly once the water recedes, making it resistant to waterlogging. In dry years, thanks to shallow groundwater, moisture rises and the land remains damp at night—a phenomenon locally called “night moisture return.” The unique soil properties and climate provide ideal growing conditions for Chinese yam, resulting in yams that are rich in nutrition and pleasant in taste.

　　Chinese yam is composed of protein, carbohydrates, calcium, phosphorus, carotene, and other components. It has high medicinal value, with a sweet, warm, and neutral nature. It is used to treat symptoms such as spleen deficiency-induced diarrhea, diabetes, nocturnal emissions, and elimination of cold and heat pathogens. It boosts energy, builds muscle, and long-term consumption strengthens the spleen and stomach, nourishes the lungs and kidneys, relieves dizziness, and improves hearing and vision, contributing to longevity. According to Li Shizhen, cooking Chinese yam with honey or boiling it into a soup is highly beneficial for nourishing both yang and yin. A common preparation method is simmering it with pork ribs—the resulting soup is clear, fragrant, rich, and sweet. Stewing it plainly with a touch of sugar makes it an excellent tonic for nursing mothers. Truly, every bit is essence, and every drop is hard to part with.

　　In recent years, local governments have guided farmers in adjusting their industrial structure. The planting area of Laizhou Chinese yam has expanded continuously, techniques have been updated, and yields have increased. The product maintains the authentic flavor of this local specialty with nearly 200 years of history, making it highly favored by people.