Prepare and bake cake in an 8-inch round pan according to package directions. Cool in pan on a wire rack for 10 minutes. Remove from pan. Cool completely on a wire rack.
Place cake on circular platter. Frost cake using white frosting. Arrange chocolate pieces in a circle in the center of the cake. Place lemon drops in single circle around the chocolate pieces. Cut orange and yellow fruit slices horizontally in half lengthwise. Arrange the thin slices around the lemon drops and around the outside of the cake to resemble petals.
Arrange shoelace fruit snacks around the cake to resemble vines. Cut leaf shapes out of the green roll-up fruit snack and arrange atop green vines. Makes 10 to 12 servings.