Black Silk Rose Cake Flowers - Reception Decoration 12 Beautiful, black roses and petals to decorate your wedding cake versatile cake flower set comes with 12 open black rose heads and 250 matching rose petals rose heads measure approximately 3 inches across and you will receive 12 of them to use as you need silk rose petals measure approximately 1 inch in diameter and you will receive about 250 sprinkle the petals all over the table or just cluster them around your cake as we did in the photo