Meanwhile make the frosting. Place shortening in a large bowl and mix on medium with an electric mixer for 3 minutes. Turn mixer to low, then gradually add the sugar, milk and vanilla. Once all is combined, turn mixer up to medium and beat for 3 minutes. Divide frosting into 3 bowls. You only need a small amount for the leaves, so most of the frosting can be in 2 bowls. Color the smaller amount green and the other 2 bowls your colors of choice. Place green frosting in pastry bag fitted with a #352 tip. Set aside. Place a large piece of plastic wrap on the counter. Spread some of one color onto it, the spread some of another color on top. Roll up the icing and twist the ends of plastic. Cut about 1/2" off one side of the plastic roll. Place that into a pastry bag fitted with the 7-petal Russian pastry tip. Spread a little bit of icing onto each cupcake, then pipe roses. Pipe leaves next. Serve immediately or store in the refrigerator for up to 4 days. Let them come to room temperature before eating.