Mine are 50/50 homemade manured compost and creek bottom soil. They get compost additions 2x a year. Link below is to several previous discussions of this question with lots of other suggestions. And you'll find even more mix recipes over on the SQ Foot Gardening and Container Gardening forums since they used raised beds a great deal. Dave Here is a link that might be useful: What to fill rasied beds with? discussions

I guess I'm the lazy gardener. We have thick sod at our place. Last weekend I started two new beds using the lasagna method. This is how I've started all my beds. First, a thick layer of newspapers and then layers of grass clippings, kitchen scraps, dead plant material (i.e. old bean plants but not tomato plants that may be diseased), chopped leaves from the lawnmower bag, and a heavy sprinkle of wood ashes, and some aged manure. You're supposed to alternate greens and browns. This pile will sink a lot by spring. In the spring, a layer of aged and composted horse manure (mixed with bedding, kitchen scraps, etc) is added to all the beds. Right now, the two beds are about 24 inches tall. Sometimes the used soil/dead plants from pots gets added. I built my first bed in 2007, planted it in 2008. I've been very happy with this system since we have plenty of the ingredients. I get the composted horse manure from a Craigslist find. Perhaps I add enough soil, wood ashes and manure to get a good mix. (We heat with wood.) I started the first bed with old grass clippings from a neighbor and kept adding different material as it became available.

Someone, please help! I am an amateur at vegetable gardening and would really, really appreciate some guidance ASAP. Thanks so much.

A while ago Al mentioned in a thread (link below) how he made a mix for raised beds. It is very nice. In my experience with raised beds over my top soil I have not noticed much difference with 6 or 12 inch beds - could be something to look into with all that volume - or build upward over time. For my raised beds I like to rob the soil from where I am leveling an area (I garden on a hill, uphill seems to be best) or from a pathway and mix with as much compost as I think it needs. The gardens/beds that I have made always improve with time and effort. I do think that spending money upfront can get you off to a faster start but I don't think that there is much of a substitute for time and management. I have not had luck with planting in bulk soil - 2x - shame on me, that could be just my luck or local conditions though. I have been meaning to try turface in a raised bed (probably a small one), I already mix in 5-1-1 and other potting mix when it is finished. Of the ingredients of the 5-1-1 if I were adding them fresh I would leave out the perlite, it is too expensive and I think it degrades in the soil (unlike the turface). Hope this helps. Best of luck! Here is a link that might be useful: http://forums2.gardenweb.com/forums/load/contain/msg0306520029215.html