Focus stacking garden flowers

I have been experimenting with the automatic focus stacking facilities afforded by the Olympus OMD E-M1.  For the uninitiated this allows the photographer to capture a series of images each of which has a very shallow depth of field and then to combine the infocus parts of the images to drive at an image in which the required part of the image is sharp, while the background remains a pleasing soft blur.  Usually this means setting up the camera on a special rack on a tripod with allows a series images to be taken, moving the camera forwards a very small amount between exposures.  However, the Olympus system automatically takes a series of shots with different focal points and then (optionally) stacks them for you.  The images below have all been stacked in the camera with the exception of the shot with two roses which gave me too much depth of field, so I selected a subset of the images and stacked them using Photoshop.  The final image shows how too many shots results in too much focus!