Use 1/4 teaspoon of ground ginger for each tablespoon of fresh grated ginger as a substitute. If the recipe calls for 1 tablespoon of minced fresh ginger, use 1/2 teaspoon of ground ginger.
Ginger root comes from the rhizome of the ginger plant, a tropical plant commonly cultivated in India. It flavors gingerbread, gingersnaps, pumpkin pie, is served with sushi and adds zest to marinades for meat and fish. It is used fresh, pickled or dried. Fresh ginger can be kept in the freezer and is sliced or grated as needed. Japanese cooks favor pickled ginger. Dried ginger is the most common form used for baking.