With royal icing, make 29 tip 103 roses with tip 10 bases; 70 tip 103 wild roses with tip 2 pull-out stamens and 56 tip 225 drop flowers with tip 2 dot centers. Make extras to allow for breakage and let dry.
To make mini-cake: Ice both sets of cookies together, then ice sides smooth. Divide both "tiers" into 8ths. Pipe tip 13 zigzag garland, 1/2 in. deep. Add tip 2 drop strings and add tip 16 shell top and bottom borders. Set aside.
Ice 9 x 13 in. cake smooth. Divide 9 in. sides into 4ths and 13 in. sides into 6ths. Measure 1 1/4 in. down from top edge of cake. Pipe tip 2 triple drop strings from division marks. Pipe tip 2 dots at points. Add tip 18 reverse shell top border.
Cut dowel rods to approximately 4 1/2 in. long (1 1/8 in. should be exposed after inserting in the cake). Insert dowels rods in cake corner measuring 1 1/2 in. from 13 in. side of cake and 3 in. from 9 in. side of cake. Position cookie "cake" on top of dowel rods.
Position flowers on cake top in "S" shape. Build up icing mound as a base for flowers behind ornament; mound roses on top. Position flowers around bottom border and add tip 352 leaves. Position drop flowers on mini cake.