Great colors and wonderful composition. The only distraction for me is the round dish looking thing in the top corner. It draws my attention and makes me wonder what it is and takes away from the focus of the flowers, but that's just me :). Overall, it's a wonderful picture.
You've made a find shot on the white flower, well lit and nice use of shadows... I don't think any of the other elements in the shot add (the buidling, red tulip, other white flower) to your "friend"'s beauty. The red tulip, because of it's color, dominates as the main subject but since it's partially covered, the composition suffers