I take it you already have them made. I just made a wedding cake with a gumpaste roses cascading down the tiers where I stuck toothpicks into the centers and built the flower around that. Then I just stuck the flowers straight into the cake – no need for gum glue, water, or anything to make the stick. They stayed put on their own.
If your roses are already made, What if you stuck them into the cake so that the cone shaped back dug into the fondant a little and then you can fill the gap with some fresh gumpaste rose petals or leaves? That way you’d fill the gaps? You can stick the flower initially with some royal icing which dries nice and hard. good luck!
Maria @ http://www.facebook.com/rooneygirlbakeshop or http://www.rooneygirlbakeshop.com
