If you are afraid the rosepetals are going to stain the sheet, you can allways bring your own sheet. I think fresh petals would be the best! They're soft and smell good. You can also have some fresh roses there to make an even more pleasant smell. If shes allergic vanilla scentet candles may be out of place.
Perhaps you can spread the petals the moment you both get there.... Buy some time by blindfolding her. Some erotic lounge music, slowly undressing her - kissing her lightly - telling her how much you like/love each bodypart as you reveal them.
Lead her into the bathroom and bathe her. (Petals are nice in the tub - some massage oil in the water makes her skin baby-soft) Do it slowly and erotic - Alternate from light touches to deep kisses. Rub your body against her. By keeping her attention she won't fall asleep.
Kiss her all over as you dry her with a soft towle. Make it erotic, but don't cross the "edge" (It's not the right moment to fist her......yet *S* )
Then you can enter the bedroom and remove the blindfold. At this moment candles should be lit, and rose petals all over the bed.
Take your time to enjoy each other slowly, make it a good time you both will remember and talk of
