Cute card, Jill! and that flower looks as if it was meant to be in black and white, don't go colouring it in now!
My background is genuinely stitched together: lots of little squares cut out of scraps, lightly glued down then stitched over. I splashed some gesso (undercoat) around where I wanted the photo to be to have it a little less 'busy' then sprayed over a mask to let the gateway appear.
Here's another page I made using the same technique, only this time I didn't take the lazy way out by cutting large squares, these
squares are only 2.5cm˛ each: