This color scheme, if you are a little doubtful about it, then don't be, go ahead if you have your heart set on it then just do it, I'm sure you will be very happy with the results.
You could even go so far and make the whole event mono-tone, you and everyone else will be amazed at the results. But if you want a splash of color then do it through the flowers, the whole color spectrum is at your beck and call.
Have a wonderful day.
