Activity 6: What potatoes need to grow

Activity 6: What potatoes need to grow

This activity is about what potatoes need in order to grow well.

You will need:

• 4 seed potatoes
• 4 large 10 litre pots (you could use buckets)
• Bits of broken plant pots or pebbles
• Soil or compost to fill the pots

Children can undertake their investigation in groups or you could complete it as a class. See the Grow potatoes investigation factsheet for equipment and investigation ideas.  

Groups: Each group can plant 4 potatoes in four separate containers, keeping one as a control and changing one variable for each of the other 3 plants.

Class: Split the class into four groups with each group being responsible for growing one potato with a different variable. For young children you could just plant a control and one or two other variables.

This investigation can be set up separately or in conjunction with the Grow your own potato activity.

Introduction

Talk to the children about what they think is needed to make a potato grow well (light, water).  Ask the children how they know this, and how they could confirm what they think.  Establish that they could remove or change one of the conditions they think the potato needs and see if it makes any difference.  Discuss the condition changes you could try, e.g. temperature, water, light, soil. Look at the Grow potatoes investigation factsheet for ideas.

Explain that in order to see whether making these changes makes any difference, you must grow a potato in the usual way as well, so you can compare them. The potato grown in the usual way is called the control. The other potato/es must also been grown in the same way with just one condition/variable/factor changed so you can see if that is what really makes a difference.

Task

Let the children plant their potatoes. Talk this through together first to emphasise the importance of ensuring that only the variable/factor is changed and the rest are the same, so it is a fair test.

Discuss the idea of a ‘fair test’ with the children to ensure they understand.

You could set up a class record or children could keep their own records. You may wish to use the Potato investigation worksheet 1 (compares a control potato and a potato with a variable changed) or the Potato investigation worksheet 2 (compares one control and three variables).

Round up

Re-cap on what you have done, question the children:

• What are we trying to find out?
• What have we done?
• What do you think will happen?
• How have you made sure it is a fair test?

Discuss how you will be recording the investigation including how often observations will be made.

Extension ideas

• Grow different types of potatoes and investigate which type grows faster and how they differ in appearance?
• You could use the Are they the same? worksheet to help record your findings.