I simply turned the dessert cups upside down and punched a hole in the center of the cup using a sharp tool. I printed up labels for the kids to apply to their flower pots.
It works best to glue the two sides of the flower together with the straw in the middle. You can cut the straw to the height you'd like. After the flower is glued the kids can add their thumb prints to the flower and then add the leaf and put the flower in the pot to dry. Adding candy to the top is optional. They can also color the top of the cup as shown below.