This all depends on the fragrances. I scent all jewelry before I ship it. I find the scent can last 1-5 months. Longer on rings if you take your jewelry off while washing your hands. I do sell refills of scent so feel free to stop by here and pick up some new scent to keep your jewelry smelling fresh!
To give you an idea stronger scents last longer then others.
Some stronger scents are: Blueberry, vanilla, chocolate, maple syrup
Lighter scents: Anything that's meant to smell like meat. So beef or bacon even cheese.So remember to care for your jewelry and the scent should last for a while!