Rainbow flowers with AmazeLab

by Fellowship Agency April 28, 2021

Gratnells has partnered with AmazeLab to create an exclusive collection of #WhatsInMyTray activities.

Watch as flowers change colour with this rainbow #WhatsInMyTray experiment.


  • Gratnells Tray
  • White flowers (you can use celery as an alternative)
  • Food colouring or ink
  • Water
  • Container/glass
  • Scissors
  • Cutting board

What to do:

  • Collect all the equipment and place it inside the tray.
  • Add water to your containers/glasses.
  • Add food colouring or ink. Use as many colours and flowers as you have (with older children challenge them to split the stem to make true rainbow flowers adding each section of the stem to different coloured water).
  • Using scissors, trim the stem of your flowers and add them to the water.
  • Keep observing the flowers as they start to change colour.

The Science:

Plants require water to survive. They take water from the ground to the leaves using a process called ‘capillary action’. This happens by water evaporating in the leaves causing a pressure change in the stem, helping the liquid from the roots rise to the surface. This is why the flowers change colour.

Big questions:

  • Are you able to identify all the parts of the plant, including the part that is responsible for allowing the colour to change?
  • What do you think would happen if you used warm water instead of cold water?

Curriculum Area: Science
Topic: Plants
Age group: KS2 – Living things (working scientifically)