I have put together my own potting mix a couple of ties in the past using my own compost and some purchased ingredients (See Project: Homemade Potting soil project), but Gary Pilarchik shows how you can use purchased materials to create a mix a much lower cost than the prepared mixes you might find in the garden store. Sure, you have to invest the time in mixing everything together, but with soil — as with food — if you make it yourself, you know exactly what is in it. — Douglas
Here are the principles for making cheap and effective garden container soil. It is prepared with organic fertilizer, lime and peat moss. I show a basic mix and a premium mix (manure). Use this as guide and save yourself a ton of money.