I'm having trouble getting the defocus node to recognise the Z pass in my renders. I have set up a depth of field in 3D view and turned on Z pass but I'm not sure where the nodes need to go to have any effect in compositor?

Also I'd like to add in color correction but again am not sure where this node needs to appear in the node tree. Thanks in advance.

The Z pass is only defocussing inside the boundaries of the Tea Caddy. I presume this because the Caddy is divided against the background? Is there a way to extend the defocus effect of the edges of the object so it fits naturally into the scene?