A plant cannot walk to a sunny spot or get itself a drink. It needs us, or the rain and the sun, to give it what it needs.
Key idea
Plants need light, water, air, nutrients from the soil, and room to grow.
Why it works
The leaves use light, air and water to make the plant's food. The roots drink water from the soil and take in a little of the nutrients there. Without light or water, the plant cannot make food, so it droops and turns pale.
Worked example: Let's think it through
Two bean plants start the same. One is by a sunny window. One is in a dark closet. Which grows better?
- Plants need light to make food.
- The plant by the window gets light.
- The plant in the closet gets none.
Answer: The plant by the sunny window.
Common mistake
Many children (and grown-ups!) think plants get their food from the soil. The soil gives water and a few nutrients. The food itself is made in the green leaves.
For the grown-up. Try it together: Plant two bean seeds in cups. Put one in a sunny window and one in a dark cupboard after they sprout. Look every day and talk about what you see.