To sprout most seeds of other plants I usually use compost in the lower quadrant of my containers, topped with an inch or two of moist vermiculite. Will this formula also work for alpines, or should I have a supply of sand or grit on hand as well?
I usually winter sow most of my perennials. Some seedlings roots will reach the compost layer before I transplant them to a growing-on container, and some won't, but it's my fail-safe; fewer seedlings dry out and die during the very busy springtime season if it's in there than if it isn't.
Thoughts on this?