Potting Soil for Growing Mountain Laurels

When we plant these mountain laurel seeds we have a choice of what kind of potting soil we're going to use. They make a premium grade which has no soil in it. It has peat moss and composted plant matter and it is quite highly organic. There is no dirt in this no sand, no soil. There is a cheaper variety which actually has sand or soil in it sometimes a lot of sand. This stuff can become compacted and it doesn't absorb water and it doesn't hold water like the pure organic does. So I would rather especially in the area that I'm going to be germinating these seeds, use the premium grade because of the moisture holding capacity.