I love the pictures and I like your use of selective colouring. I understand why you chose to create a "fantasy-land" sky and although it isn't my style, I think you've accomplished what you were working for. Nicely done!
Thank you for the comments/critiques.
I agree that #2 has a lot of red, but I loved the roses and I hated to manipulate the plant itself to get a cleaner shot.
#3 was not completely focused when taken, so I went soft-focus in my photo-editing.
I'll try #4 as a vertical crop. Thanks...
I edited the last picture and I think the colouring is more correct, but it still seems flat (even with all of my contrast changes)! So I converted it to B&W and cropped it a bit and I like it so much better!
The compositions of the photographs are good, but the images seem flat to me. Is your friend shooting digitally? If so, I recommend tweaking the levels in a photo-editing program to add depth.
The last picture is my favourite.
These were taken months ago, when I was still shooting with a basic Canon point-and-shoot. The file sizes are greatly reduced and the colours a little weaker than the full-size photographs. Comments and critiques welcome!