Sophia and Olivia belong to a 4-H club that I'm leading for homeschoolers; and one of our major activities is doing the Junior Master Gardener program.
The first chapter of the book focuses on "Plant Growth and Development" and has a variety of activities for youth to do as a group as well as individually at home.
One of the activities to do at home focused on turning a white carnation different colors. The book suggested doing a red, white, and blue carnation. Since it was close to Christmas, Sophia chose to do a green and red carnation; and Olivia chose to do a green and white carnation.
The first step was to cut the stem in half using a knife or scissors. (Had we tried to do a tri-color carnation, we would have had to split the stem into thirds which would have been quite difficult.)
The girls filled two different cups up with water and then added food dye to each one.
They placed their carnations into the water and realized that they would need to affix the stems to the side of the cups if the flower was to stand upright. (Otherwise, the flower fell to the side and the bottom of the stem came out of colored water.)
Sophia hypothesized that the leaves would start changing colors the same day, while Olivia thought that it would take until the following day when her flower would change colors.
Within a few hours, the tips of the carnations were changing from white to either green or red.
We all thought that the the flowers would have an all-over color change. However, we left the flowers in the colored water for well over 1 1/2 weeks, but there was still white on all of the petals. (Thus, the flowers also look a bit wilted since we were curious to see how much the petals would change in color.)
What we did notice, in Sophia's carnation in particular, was that the petals had a deeper color around the edges and had rows of coloration as one looked from the edge to center of the flower.
It was an interesting experiment to do, and showed us all how the stems transport the water from the glasses to the petals.