Nada...
just the mulch that's applied to the gardens in the spring. It truly does reign here in the garden in winter. And I love seeing the green (although slightly purplish) leaves in the snow.
And the reason why I said my plants have withstood only 6 years is that 7 years ago we moved to the new house and I had to start all over.
You plant sage, you should have it until you die. It should grow into a gnarly bush with a woody trunk if you leave it be.
BTW: my grandmother up to the last days of the big family holiday gatherings, was still pulling out my great-grandfather's sage from a jar to put into the oyster dressing. Granted by then it probably had no taste, but the memories of that jar coming out of the pantry and watching my grandmother lovingly crumble it into the basin are etched into my brain.