Free images results:

Background Plants pictures, stock photos and images


Barley Stock Photography
Author: Lsk
Waterfall Royalty Free Stock Images
Author: Mshake
Flower Stock Photos
Author: Fotohmmm
Red ivy Royalty Free Stock Image
Author: Glinn
Ivy Stock Photography
Author: Knips
Thorns Stock Photo
Author: Photong
Gourd art Stock Images
Author: Glinn
Tree Stock Photos
Author: Marangon

Also, here are some commercial RF-licensed images that match your search criteria:  
Plants Royalty Free Stock Photos
Author: Jerz