The only organic wonder treatment is compost or manure! Sorry

I can offer my experience of my front garden a couple of years ago....it was also very dry and very stony (it's still stony!) and quite compacted. Not a single worm was in sight. I watered it liberally then covered the whole area with old cardboard boxes (Tescos does come in useful sometimes!), which I thoroughly wetted again. Then on top of that (whilst stil all wet), I poured on a *load* of horse manure..more damping down, and finally covered the manure in cocoa shells to make it look nice. And then left it, only wetting it all again if there was no rain. The horse manure came with loads of little red wiggly worms and they did all the hard work of breaking up the soil. I did have to remove a positive pasture load of grass that sprug up from the horse manure but that was all the work I did (not too back breaking!). I got very worried about some strange fungus that quickly took over about two weeks after I put it all down, but I was told that it's fine and it's a natural fungus that grows on manure. It all died down and was reintegrated with the soil.
I did all this towards the end of summer and just left it all Autumn and Winter and then planted it in the Spring. Very little effort. The following summer (last summer) the front garden sprang into life and produced massive swaithes of flowers (it's a Cottage Garden...well...that's what it's supposed to be, it's all rather more Wild Garden than it technically should be I think!). Loads of worm activity, loads of wildlife. Lots of crumbly soil.
I can't remember exactly what green manures are recommended for growing on compacted soil but I think that clover is one - the idea is that their roots also break up the soil. The more work the worms and roots do, the less you have to do!
Alcina