I bought large bags of Kellogs Potting soil at Walmart for $4.97. If you have access to a P/U truck you can get compost very cheap if you don't need it delivered.

Which is better for container growing? Compost or potting soil?

I only grow tomatoes in pots. I mix the compost and potting soil in equal amounts.

Tomatoes4ever, I make potting soil for some of our potted perennials - mostly mints.

About 3 or 4 years ago, I purchased a small roll of 1/4" hardware cloth and attached it to a board frame with lathe. I use this screen to remove stones from garden soil and to mix in the other ingredients as I go along. The frame fits over a wheelbarrow.

A local farmer will load a pick-up with well-aged manure for $4. It is a mix from cows and horses and pretty good stuff. I purchase compressed peat moss at wholesale for $11/3.8 cu ft. Garden soil is obtained from a fertile location. These 3 ingredients are mixed in equal amounts and run thru the screen 3 shovelfuls at a time.

The mix will have weed seed but if I don't count labor and garden soil what do you suppose . . . my cost is maybe a dollar for every time I fill the 1/4 yard wheelbarrow. This year I added vermiculite but I'm going to need to find a less expensive source and prefer perlite, anyway. It certainly improved the weight of the mix, however. I've also used sand in the past but my garden soil has plenty of sand in it and that component wouldn't reduce the weight. With or without vermiculite/perlite, the mix has worked well.

ATTRA, the National Sustainable Agriculture Information Service, has "Recipes for Growing Media" information. Mixing your own doesn't take long and if you can find a nearly free source of composted manure, is a great deal cheaper than purchasing potting soil. At the price of bagged potting soil, it may be a little cheaper just to buy all the ingredients in the bag and mix them yourself. Or, a reasonable alternative may lie somewhere between these 2 approaches. Check out the recipes.

Steve

Here is a link that might be useful: Recipes for Growing Media

The compost I get is from a Dairy Farm and he began his compost sideline after he developed a blend for his wifes Roses. She is a Rosarian as well a a Rose judge.

Local nurseries sell potting soil mixes for around $20-25 a yard. If you have a truck, trailer, or way to pick it up it's way cheaper than bagged stuff. Having a big compost pile and working it right could be the way to go, good info on the /soil forum here.

Espoma is good http://www.amazon.com/

There is organic and then there is organic. If you don't heat the stuff to rid the bad. I used to be certified organic -- i still try but sometimes you need the good stuff like Hudson uses. Now mind you -- you only have to be 70% organic to be legal which I never could understand. I may have to delete this post or if the moderator wishes to do so as it could be a can of worms-- everyone has their own opinions.

A couple of comments above are right on the money. Large quantity (bulk) buying...is always a great idea. Never use native soil in a pot. Never use the "moisture control" variety...touted by one manufacturer. Mixing your own (as sey says) is a fun thing to do if you have the time, and you like the "scientific experiment" angle.