There is nothing easy about growing white sage; beginning with its seeds. White sage seeds are tested to a germination rate of twenty percent. Seed with this low of a germination rate are considered too old to use! Being a desert plant, white sage seeds will germinate in a few weeks or 80% will wait for six months to a year, maybe many years. This adaptation insures some white sage seeds will be ready for the next rain, even if ten years away!
This survival strategy is great for the desert, but makes germination uncertain in a greenhouse. Our cell trays are not a help, because we end up with dead cells or ones with too many seedlings. To insure a strong crop of white sage for the spring 2013 season, we resorted to an old fashion method of sowing seed. This means each and every seedling must be carefully transplanted to a cell. Being a species plant, there is wide variation in seedling size.
We carefully plant like sizes together. Watering is always the issue with white sage, well drained potting soil or garden soil with sand added are necessary. Wet soil can cause root rot quickly, never let white sage stay in wet soil!