It's not easy being green

Date posted: 26 August 2013

Take a look at our barley crop growing away nicely in the Botanic Gardens... the seedlings are thriving with healthy green leaves and a strong and developed root system.

The colour of the plant leaves are a good indicator of how healthy the plant is. The greener the better!

The green colour is caused by chlorophyll in the plants leaves.

Chlorophyll has the job of soaking up rays of sunlight. Not just any sunlight. Light is made up of many of different colours (think of a rainbow!). The plant soaks up the red and blue light as this is the most important for them. Green light is reflected as it is not needed – so this is the colour we see.

Once the plant has absorbed light it can photosynthesize... Photosynthesis is a fancy way for saying the plant is making its own food.

Photosynthesis involves a reaction which takes sunlight, water and carbon dioxide and turns it into sugar and oxygen. The sugar is transported all around the plant and used as energy to carry out day to day living - the oxygen is released into the air (so we can breathe it!).

Here’s an experiment you can do at home! Try putting a healthy plant in the dark... what happens to the colour of the leaves? Do you think this is good for the plant – will it be making its own food?

Watch the video below for more information on photosynthesis.