Are you peeling your ginger before storing it, or keeping it whole with the skin on? That actually makes a difference. The skin acts as a natural barrier, so if you're buying it already peeled or cut, it's gonna deteriorate faster no matter what you do. Whole ginger root with the skin intact will last way longer than pre-prepped stuff.
For long-term storage without freezing, the key is honestly getting it into a cool spot that stays consistently temperature-controlled - like a pantry or cupboard rather than relying on the fridge. Wrap each piece loosely in newspaper or a paper bag so it can breathe, and check on it every week or so. Some folks keep theirs in a root cellar or basement if they have one. The main thing is avoiding that humid veggie drawer situation where moisture builds up and encourages rot.
If you want it to last months and you're cool with using frozen ginger in soups, stir-fries, and tea, freezing is honestly unbeatable. Peel it, slice or chop it into manageable pieces, and freeze on a tray first so the pieces don't clump together, then transfer to a bag or container. It lasts basically indefinitely that way, and you can grate it straight from frozen when you need it.