Rhubarb is one of the first spring vegetables to pop up. The edible portion of the plant is called a petiole: a thick, red, celery-like stalk. Rhubarb petioles are low in calories, and rich in vitamins and minerals. But they are also exceedingly sour. So how did this tart vegetable become the basis for pie?
Rhubarb was a medicine long before it was considered food. The plant originates from China and Tibet where the root has been used to relieve constipation and other ailments for at least 4,500 years. In Chinese it is called “da huang,” which means “big yellow”—a reference to both the size and power of the rhubarb root.