What to plant after digging up spuds

If you've got heavy clay soil, had a summer drought, hot weather and no water at the plot the answer is literally sod all as it's now impossible to cultivate:

 

Aww Scrunge

I'll send some of this rain up your way, mind you, even after the downpour i've still got big cracks in the clay.

 

I'm not sure if that bed will be usable this year as those boulders are up to 450mm across and like rock armour.

 

I reckon it will break up if you tread it just as its drying after a good downpour?

Might be best left open for the winter to have a crack at it, but otherwise how about a green manure over winter? Something with fibrous roots is suppose to break up clay I think (from memory) and Field Beans springs to mind (same dodgy memory though!)