Hi there,
I planted 6 seeds that were a couple of years old this spring. I soaked them in warm water with a splash of seaweed emulsion overnight before planting. The seed coating will absorb water and look like a frog egg with the seed inside a clear gelatinous coating. Then I surface sowed and sprinkled a very thin layer of fine vermiculite over them and watered lightly. 5 of them germinated within about a week and are still doing fine. I've done the same with all my other salvias and many other seeds and consistently have very good results.

Thanks danita. I have a few left from those I tried to germinate so I will try your technique.