Open photo of flower in photoshop

Duplicate layer

filter-convert to smart filter

filter-blur gallery-path blur

On the right hand side of the screen there will be a Blur tools panel and on the photo a blue line with a white circle at each end. click (with the mouse which looks like a pin now) on a white circle and move the mouse to where you want to start the path then click into the other white circle and move the mouse to where you want the path to end. There is a centre smaller white circle in the middle and you can click inside and drag away to make a curve to the path. The amount of blur is determined by the speed slider in the blur panel. If you want to create a second path then make a single click with the pin mouse where you want it to start and then move the mouse to where you want the path to end and make another single click. Again you can use the central circle to make a curve by clicking in it and dragging out. If you make a mistake and want to delete the path then click in the white circle and press delete on the key board. You can change the direction of the path from where it finishes, by clicking into the white circle at the end of the path and a small red line appears with a red arrow head. Then click into the white circle at the end of the arrow head and move mouse to where you want it to end and use the middle white circle to create a bend in the direction if required. When happy click OK in options panel.

A last thought is if you are on the top layer with the blurred flower and chan be the blend mode to overlay you get a slightly softer version of the original image. This is slightly better than just duplicating the original photo and using overlay mode.