When ginger has gone bad, the root will give off a few signs when that it’s ready to be tossed in the trash. If it has gone longer than a few weeks on the counter or a few months in the fridge or freezer, you’ll want to conduct a visual and aromatic inspection before using it in your recipe. The outer layer of the ginger should be papery, while the interior should be firm and yellow. Ginger that appears soft, wrinkled, or has visual signs of mold has gone bad.
If your ginger passes the visual inspection test, you will also want to take note of the ginger’s smell and flavor when you use it. Ginger that is low-quality or spoiled will not be as pungent in taste or aroma, per Fresh From the Gardens. If your ginger is bland but not moldy, it is still safe to eat (though it might not be as fun). Just don’t expect a bright pop of flavor in your stir-fry or cocktail.