When shooting flowers, I usually prefer straight photography with only selected tonal adjustments. Flowers, after all, possess enough beauty of their own that their photographs generally appear best with only minimal post processing. In some cases, however, a painterly effect can enhance their appearance. Aside from the use of Photoshop plug-in filters, this can be accomplished by processing the photo in Corel Painter 12.
To achieve the above photo, I first started with the straight photo below to which only slight tonal adjustments had already been applied in Photoshop.
I then opened the above photo in Painter, and after having chosen Quick Clone from the File menu, picked Smeary Camel Cloner. I then ran Auto Paint, making sure to choose Image as the clone source. After ten minutes, I had the photo shown below.
This photo was much too "arty" for my taste, so I returned to Photoshop and opened both it and the original image. Choosing the heavily retouched photo from Painter, I selected Apply Image from the Image menu. I applied the straight image to the retouched image at 70% with Pin Light selected as the blend mode. That gave me the photo shown at the top of this post which, I feel, has a slight painterly effect but nothing so pronounced as to be objectionable. What constitutes such states as "arty" and "ojbectionable" are, of course, a matter of personal taste and some photographers might opt to apply the original image to a greater or lesser extent and might find different blend modes more suitable for their purposes. It's largely a matter of trial and error.