Testing Variables in Seed Germination

None required — seeds, water and everyday household items only.

Disposal: Seedlings and growing medium can go in garden/organic waste or be planted outside.

Materials

• Fast-germinating seeds (e.g. cress, bean or pea seeds)
• Cotton wool or paper towel
• Small containers or clear plastic cups
• Water

Steps

1. Set up several containers with damp cotton wool or paper towel and a few seeds in each.
2. Change exactly one variable between containers — for example, one in a dark cupboard and one on a bright windowsill, keeping everything else (water amount, temperature) the same.
3. Check and water the containers daily, recording how many seeds have sprouted and how tall they've grown each day.
4. After about a week, compare the results between the different conditions and discuss which variable(s) affected germination.