I would like to build a poured exposed aggregate retaining wall with two levels in my back yard. Right now my back yard is a hill. The ground is flat for 4 feet then it proceeds uphill to the property line. I'm having the hill dug out into the rough shape I need. It's alot of dirt (mostly clay) to be removed. Neighbours have done their retaining walls in Allan Block. My driveway and sidewalks are aggregate. Now what? I don't want a contractor for the whole project. I need to piecemeal it due to cost and do what I can on my own. The aggregate won't cost me anything, but once I've dug out what's the next step...for a base etc. I intend to hire someone to put in the forms and do the actual pour.

 

I am completing a similiar project. I had a 65' x 2 1/2' high wall to build. I first looked at Allen Block, Keystone, & Pisa Wall Stone. It didn't have a custom enough look that I wanted. I ended up building the wall up from 8" x 8" x 16" Cinder blocks. I found that the cost of the blocks and the concrete to fill them kept me well below the cost of the Landscape wall stone. To finish it off with the custom look, I used a Veneer Stone made by Eldorado Stone. Another manufacturer is Cultured Stone. It was very easy to make it look like it was done Profesionally. I am finishing it off with a wall cap from Arto Brick, a large 10" x 4" x 24" long Pre cast cap. I went this route so that I could do all of the work on my own and work at my own pace. I think if you cut out the contractor to set up your forms, you'll easily be able to fit the Veneer stone into the Budget.
check out http://www.culturedstone.com for ideas. I Sorry that I could not answer your direct question, I feel that an exposed agregate wall may not be an option unless you are going to mortar or epoxy the agregate stone.