Just buy a bale of peat moss, earthworm castings, compost, perlite or rice hulls, and some dolomite lime, and mix it together and allow it to sit for a while, then you're good to go. I like to use between 45-55% peat moss, 25-35% perlite(want to start using rice hulls though, they sound interesting), 15-25% of a mixture of quality compost and earthworm castings, and dolomite lime at 2 Tbs per gallon of soil. It's a pretty well known recipe, I think, but works excellent. I feed this type of mix with ewc and guano teas, also AACT's.