I have heard of bud being grown in aged cow manure and sand, 50/50.
Not suggesting this by any means, but once the stuff has cooked down a bit it can be very useful, especialy when mixed with other stuff. Robby makes a good call. If you want the sky to be the limit though It's got to compost at least a year IMO.
Are you getting by the load (trucked in) or by the bag?