Opened flower source photo, cut out main flower, placed on layer duplicated a few times rotating each, moved to my photo on own layer
step 3 of 5
selected flower source foreground, moved to my photo as seperate layer.
step 4 of 5
Used stamp tool, covered pops and car, placed several layers of flower heads adjusting size with free transform
step 5 of 5
Put flower foregound on top layer, used eraser at 60% transperancy and cleaned edges a bit. Adjustment layer (color balance), and brightness lowered, contrast increased.