Question
i bought some white roses for v-day if i add res food coloring will the change color over time  

Answer
Hi David-

I'm not sure what professional florists use to change white flowers to colored flowers but the look is always artificial.  If you added food coloring it would change the color immediately, but not over time.  The color of roses comes from the rose genes, dna.  

Have a good day-

Carlene