Create a duplicate layer - Layer>duplicate layer. This layer will be in the Layer palette ABOVE your original.
With the duplicate layer selected - Filter>Blur>Gaussian Blur, set on about 27
In the Layer Palette, change the layer mode from Normal to Soft Light
Ta DA! You may have to reduce the saturation a little. Ctrl+U will bring up the saturation dialog box
Nice, but boring flower photo. Duplicate the layer
On the duplicate layer: Filter>blur>Gaussian blur A LOT, like 27. Change the layer mode to Soft Light
Look at how the highlights in the white petals now glow!