How to get defocus to 'bleed'

The defocus node – it blurs things in the foreground fine, but how do you get it to bleed into the midground – see the included image – notice the hard edges of the objects in the foreground – how do you get them to blur in the midground?

select your camera and go to the camera properties buttons. under the “display” tab, check the “Limits” box, then on the “Depth Of Field” tab play with the setting labeled “distance”. Do this from a side view of the camera and 3d scene and you’ll see a little x on the camera’s limits line that hones in on the desired focal area. This will cause both fore and background objects to blur.