Polygonum cuspidatum is not only ornamental, but also edible. The tender stems are vegetables and the roots are cold drinks. Cool in cold water (especially in the refrigerator) is called "cold drink", which replaces tea to relieve summer heat. Its juice can dye rice noodles and has a special flavor. Eating method is also called "sour soup stick" because of its sour taste. Polygonum cuspidatum contains Polygonum, organic acids, glycosides, polysaccharides and so on. Has the effects of clearing away heat and toxic materials, cooling, relieving diarrhea, invigorating stomach and promoting digestion.