Sign in

← All revision topics

English variety

What plants need to grow: water, light, air and space

Around age 7 · Usually taught in ⁨Year 2⁩ · Free

Aprende

  1. A plant is a living thing. To grow, it needs four things: water, light, air and space.

    lightwaterairspaceplant
    What a plant needs to grow

  2. The root takes up water from the soil. Without water, the plant dries out. But more water is not better. If the soil is always waterlogged, the roots drown: they need air too.

    Sunlight reaches the leaves. With light, the plant makes its food. A lamp that is switched on gives it light too. Without light, it becomes weak and yellowish. A plant by the window grows towards the light.

    comes inarriveslightwindowplant
    Light reaches the plant

  3. The leaves take in the air around them. The plant needs it to live.

    takes up watertakes inlight and air
    Each part takes what it needs

  4. A plant also needs space. Its roots and leaves grow and need room. If lots of plants are very close together, they shade each other and take each other’s water.

    too closewith space
    Plants need space

  5. A plant does not eat soil. The soil holds the roots and stores the water. Each plant needs its own amount of water: a cactus, very little. If one of the four things is missing, the plant grows badly.

Worked examples

Ejemplo 1

Gus waters his plant every hour, because he thinks that more water is better. The soil is waterlogged and the leaves are turning yellow. What is happening to the plant?

too much water
  1. The plant needs water, but not that much.
  2. With waterlogged soil, the roots have no air.
  3. The roots drown and the leaves turn yellow.

It has too much water. It needs to be watered less.

¡Ojo! Many children think that the more water, the better.

Common mistake

Ejemplo 2

Mara has a plant in a corner of the shop, far from the window. She waters it, but it becomes weak and yellowish. What is it missing?

windowplant
  1. The plant has water, air and space.
  2. But in the corner the light does not reach it.
  3. Without light it cannot make its food.

It is missing light. It needs to be put next to the window.

¡Ojo! Many children say it is missing water, because it looks droopy.

Common mistake

Ejemplo 3

Julie sows twelve seeds in a small plant pot. All of them sprout, but the plants come out thin and short. Why?

in a plant pot
  1. The twelve plants have water, light and air.
  2. But there is not enough room in the plant pot for so many.
  3. They shade each other and take each other’s water.

They are missing space. They need to be separated.

¡Ojo! Many children think that the closer together they are, the better they grow.

Common mistake

Un reto para pensar

Look at the plants in your home or your neighbourhood. Are they in the sun or in the shade? Do they have room? Draw one and what it needs. Do not pull up any plant.

Practica

Rondas de 10 preguntas. Elige el nivel:

Next topic: From seed to plant: germination (an experiment) →