As part of our unit on plants we attempted to dye some white carnations.
First, we added dye to the water in three of the vases, split the stems (to speed up the intake of dye), and then put one flower in the plain water (control), one flower in each of the vases of dyed water and another flower in both of the vases (half of the split stem in each vase).
We then waited, and waited, and then waited some more. We were supposed to see some results within the hour but we observed only slight red colouring in the flowers after several days (you have to look really closely at the photo).
Next time we would try adding more dye to the water to make a stronger solution and also use warm water to fill the vases. We might also experiment with other colours of dye to see if that made a difference.