What do you do when your grocer has a selection of stunning white flowers on sale all at the same time? Why – you do a nature science experiment with them of course! You may have seen our recent colour changing flower and bi-coloured flower experiments with gerbera daisies. This time I thought we could try dyeing several varieties of flowers (gerberas, lilies and chrysanthemums) at once to find out which flowers absorbed the most vibrant colours. We also decided to try both red and blue food colouring, to see what worked best.
The set up for this experiment is simple. You just need:
- several varieties of white flowers
- food colouring
Step One: fill vases with water.
Step Two: Add food colouring to each vase.
Step Three: Trim your flowers, and add some to each vase.
Step Four: Take a moment to pause and study the flowers. They are so beautiful, after all!
Step Five: Wait and see what happens!
The chrysanthemums were showing pretty flecks of colour in less than an hour. (Quick enough that you could do this as a cool gender reveal activity at a baby shower – provided you kept the water in the vase hidden of course…. But I digress!)
The next morning, here’s how the two vases looked!
This experiment was slightly unfair as none of the red lilies had opened, but I’d still say the chrysanthemums were a clear winner. They absorbed colour the fastest, and the most vibrantly, and it didn’t appear to have caused any wilting at all.
Interestingly, whilst we’ve had success with gerberas in the past, they didn’t absorb very much colour this time. It’s a bit hard to see here, but I also found it interesting to note how much the lilies’ stems and leaves changed colour, demonstrating that transpiration delivers water to all the areas of the plant, not just the flowers.
Fun Science Fact
Flowers absorb water through a tissue of thin tubes found inside the stem, called the xylem. Water is transported up the xylem to the various parts of the plant, including the flower, leaves and stem. One of the ways that water moves up the xylem, is a process called transpiration. Transpiration occurs when sunlight evaporates water from the flowers, leaves and stems. This evaporated water loss creates a vacuum at the top of the xylem, encouraging water to be sucked upwards from the roots (or in this instance, the cut stems) to fill the empty space. This is similar to the movement of water up through a straw when someone is taking a sip.