The Japanese pickled ginger served with sushi is called gari. It is a type of tsukemono, or Japanese pickled vegetable, made by marinating thin slices of ginger in sugar and vinegar. In English, it is also commonly called sushi ginger or pickled ginger.
Young ginger is preferred because it has tender flesh and a naturally mild sweetness. Traditionally prepared gari is pale yellow or may develop a delicate pink tint when very young ginger reacts during pickling. Commercial versions are sometimes colored pink with beet juice, red perilla, or food coloring, especially when mature ginger is used.
Gari is served alongside sushi and is commonly eaten between pieces to refresh the palate. It is not the same as beni shoga, another Japanese pickled ginger that is usually cut into thin strips and colored red from plum vinegar. Nor is gari a sushi ingredient like nori or rice; it is a condiment served separately. Its sweet-tart flavor balances the richness and saltiness of sushi.