Here we have some green hydrangeas...They're okay, but add a little pink to them and they get a little more dimension.
It's subtle here, but you can make the secondary color darker if you prefer. Some types of flowers are lighter at the base of the petal and are sometimes colorless at the center compared to the edges of the petals.
Adding different colors will give a depth to the flowers and make them pop a little.
Kara Buntin owns A Cake To Remember LLC in Richmond VA, and cake supplies online at www.acaketoremember.com and www.acaketoremember.etsy.com