I have grown thousands of plants from seeds over 40+ yrs, and although never recorded results, think germination broke surface in min 1 week through 2 weeks. I recently planted inside some salvia seeds harvested by a friend 2 yrs ago.and they surfaced in 3 days. Are salvias particularly precocious so this is normal?
There are many different species and cultivars of Salvia. Do you which particular type you seeded? Individual species vary in the time it takes to germinate from seed (up to three weeks for S. officinalis, 10-14 days for S. lyrata, for example). A three day germination sounds quick, but the rate of germination can be affected by several factors: temperature, moisture, freshness of seed (viability), and even depth of the seeds, as they need oxygen to germinate. Any combination of those factors could affect your germination rate.