I grow a lot of Salvia from seed here in the UK. Here I start annuals off about this time of year (and the perennials get started off in April). Apart from the smaller seeded species I use the baggy method for germination as this takes up less windowsill space in a warm room (20°centigrade). Germination usually starts at five days with potting on taking place at two to three weeks. Initially I pot several seedlings in a 45 millimetre pot (saving space again) before potting on individually about three weeks later. For the initial potting up medium I use coco fibre/vermiculite mix as this makes it easier to separate the seedlings when the time comes to pot up individually.
As far as light goes I have no problems relying on natural light in an appropriate windowsill so beyond that I cannot comment.
Results wise (depending upon conditions once the plants are moved to the greenhouse in April) S.coccinea is in bloom by early/mid June, likewise S.miltiorrhiza with S.algeriensis a couple of weeks later. S.splendens Yvonnes Giant seems to take till mid July to bloom and S.urica is a late summer bloomer here.
Of the perennial species S.patens can be treated as an annual in terms of timing and (my) growing regime and will usually be blooming well by the end of June/early July (weather conditions allowing).
