How We Did It
To prep the flowers, I cut off the ends of the stem so they’d drink the water faster, then placed the stems in cups of water. I just happened to have the right number of flowers to do all the colors of the rainbow and have one left over to leave white, so we could compare the difference.
I used paste food coloring because it was what I had on hand, but the liquid kind works just as well. The only trick with the food coloring is that it helps to use a lot! I mean, really a lot–the water should be dyed a nice, deep color.
And then we came back just hours later to find that our flowers were already starting to turn colors! We kept checking on our flowers throughout the day and watched the color deepen and spread. Some flowers turned out more vibrant than others, and it was really interesting to watch the patterns the colors make as they travel through the flower petals.