One of the problems with compost is the weight. It much heavier than say peat moss, which is a crappy, dead, component of most bagged potting mixes.
Actually, I found this product to be the best potting soil mix I have ever used. With outdoor plants in the ground, I mix with the
native soil and my own compost. In pots, I use just this mix. Here it is:
PVFS Organic Potting Soil
Truly unique, coconut fiber-based potting soil. Besides having the benefits of coco fiber, also contains beneficial mycorrhizae fungi that are beneficial for
root systems. The beneficial fungi in this mix are only viable for 2 years.This organic mix is an excellent all-around potting soil. In addition, it contains other great organic ingredients including worm castings, bat guano, bone meal, soybean meal, soft rock phosphate, greensand, fish meal, blood meal, langbenite (K-mag), bark,
diatomaceous earth, perlite, and kelp meal. Beware of other potting soils claiming to be "organic", but which contain non-organic materials. Currently, no laws exist that regulate the organic status of potting soils.
http://www.groworganic.com/item_PSO255_PVFSOrganicPottingSoil15CuFtBag.html?xKey=512078 http://www.groworganic.com/pdf/label/PSO255-b.pdf