In certain regions of China, you may encounter a peculiar sight: a stone carefully placed on top of a watermelon. At first glance, it may seem like an odd or random action—perhaps to keep the watermelon from rolling away or to protect it from curious hands. However, there is a much deeper secret behind this practice, one that is linked to the sweetness of the watermelon.

During the day, the stone absorbs heat from the sunlight, shielding the watermelon from the intense heat. As night falls, the stone gradually releases this stored heat, creating a temperature difference that helps stimulate the ripening process. This natural temperature fluctuation encourages the watermelon to become sweeter over time.

This simple agricultural trick may seem modest, but it demonstrates a profound understanding of nature and its effects on crops. By harnessing the power of temperature and the environment, farmers can enhance the natural sweetness of their produce, showcasing their deep connection to the land and its rhythms.