SPRINKLER TALK FORUM - You Got Questions, We've Got Answers

It seems everything I read is geared toward below surface valve box installation. My situation simply can't accommodate this. I'm dealing with a deck (a first floor deck with a second floor deck that partially overhangs). Below the deck there is a very small bed that's just not large enough for a normal valve box and it's already planted completely. At the front of the property are a few large containers as well. Due to these large variances in elevation, I've split the system into 3 zones. Thus, I have a 3 valve manifold. Again, other than the small bed at ground level, all other ground level surfaces are cement. How do people install valves above ground? Is there a commonly used product or solution for this? I was planning on simple building a small bed of rocks under the deck and placing a normal valve box on it. Is that OK? Are there better alternatives that anyone knows about or has experiences with? Frost/freezing is not a concern.