Have heard it said that to start your lil friends early all you need is a flat, damp potting soil and a sunny window or grow light.
The question is, why any light at all if the room temperature is warm enuf. After all the little guys sprout under 6" of dirt in many instances and the last I heard that let in very little light.
I ask this because I am not at my "dahlia house" during the week and fear for fires in this old house lest I leave a gro-light on.
Thank you, ML