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How to: colour flowers


Photo - Linda Ross

The stem of a plant works a bit like a straw, sucking up water for its flowers and leaves. To see how this works, try out this fun experiment at home and watch flowers change colour.

What you need


food colouring (we chose blue, green and red)

clear vases and/or bottles.

white flowers (carnations are best) or celery



What to do

1. Half-fill three vases or bottles with water and mix a different food colour into each of them.

2. Cut the stems of the flowers or celery so that they are about the same length then place a few into each vase.

HINT: to speed up the colouring, cut the stems short and at an angle

3. Leave the plants in a brightly lit spot out of direct sunlight and watch them change colour over the next few days.


Photo - Linda Ross

How it works

For a plant to stay healthy water has to reach all parts of it. Water and dissolved minerals are carried from the roots up through the plant by vascular tissue called xylem. Xylem tissue dies after a year - the rings that can be seen in a tree when it is cut down are the remains of old xylem tissue. You can see how the water moves through the xylem by the way the food colour reaches the flowers in this experiment.


Photo - Linda Ross

Text: Isla Barlow

About this article

Author: Isla Barlow