There WERE also flowers, of course…

I had a go with the focus stacking in CS5. Works actually surprisingly well, I must say.
The procedure:
1) shoot a number of pictures with different focus points (keep aperture and exposure the same in all images)

All 6 images D700, ISO200, 1/250 sec @ f/8, Tamron 90mm macro

2) open images in Photoshop
3) Go to File -> Automate -> Photomerge
4) The window below will appear without the red circles (they are points of attention) and without the filenames in the middle column, but WITH the box “Blend images together” checked by default. That last one is the one you want to uncheck, because you don’t want Photoshop to flatten your image, yet, in case you want to do some adjustments yourself. Click “Add open files” to add the files you opened into the middle column. If you have more files open than the focus stacking requires, you can select and remove them from the list with the remove button.

Photomerge window in Photoshop CS5

5) Click OK and Photoshop goes to work to put all your separate files together in one layered file.
6) Select all the layers from the layer palette and go to Edit -> Auto Blend Layers. The window below will pop up. Stack images is the default selected, and all you need to do here is…

Stack images

7) click OK and Photoshop will go to work for you once again to figure out all the sharp parts in all the layers. It’s quite effective, and at least with the images I tried pretty accurate. After the work you will see something like this in your palette layer, except for the Layer 1 and Layer 2. Those I added afterward for some minor adjustments from my part still (which is why you don’t want Photoshop to blend layers together all the way in the beginning!)

The layer structure after Photoshop has processed the images

The end result in my case was this:

The end result after all the hard labor is done