Using food colouring to change the colour of a flower
White spray carnation flowers, vases, food colouring, water
Put different food colouring into each of the vases. Add the flowers to the vase and what them take on the colour of the water. It takes minutes to set up and can be run over a few weeks.
See this website for instructions & how it works! http://www.stevespanglerscience.com/experiment/colorful-carnations