You can move pictures yourself (so you don't have to wait on someone else to).
Once you click on the picture you want to move, scroll to the bottom of the page.
You should see these options:
Click on move this image to another plant.
Using a picture of mine as an example, this will pop up (mind you, it'll be the picture you want to move instead).
Type in the plant name you want to move it to and this'll appear (I just typed in a random daylily name to show you what'll appear):
Select the plant you want to move it to and hit submit. You'll get a notification once it's been moved.