How Plants Drink

Children will learn how plants absorb water and nutrients.

Birds Nest

Lesson Objective

The children will observe how water and nutrients are delivered to all parts of a plant.


What You'll Need

  • Celery stalks – 1 per child
  • Tall clear plastic containers – 1 for every 4 stalks of celery
  • Water
  • Food coloring – a variety of colors for fun comparison

What To Do

Note: Before distributing celery to children, make a fresh cut across the bottom of each celery stalk (flower stem or cabbage end).

  1. Distribute the celery to the children and allow them to observe the celery stalk. Activate background knowledge about celery by discussing what it is, where it came from, what it needs to live, where the bottom and top of the stalk are, and how plants get water (see Did You Know?).
  2. Tell the children they will be learning how plants get water. Ask the children to observe their celery and share how they think the celery “drinks water” – have them make predictions.
  3. Demonstrate placing several drops of color into the water and stirring the water to mix the color evenly.
  4. Assist the children with placing several drops of food coloring in the container and allow them to do the mixing.
  5. Demonstrate how to place the stem of the stalk in the water and have the children follow along.
  6. Tell the children to observe the stalk in the colored water and then discuss and draw/document what they see.
  7. Allow the celery to soak in the water overnight. The next day, have the children observe, discuss, and draw/document what occurred.
  8. The leaves should begin to show some color. Have the children share their thoughts about what is causing the stalk/leaves to change (see Guiding Student Inquiry).
  9. Continue to observe the celery over the next few days recording the intensity of the color on the stalk/leaves.
  10. Remove the stalks from the containers and have an adult slice the stems to observe inside the stalks as well.  Discuss/draw/document.

Guiding Student Inquiry

  • Explain what has happened to the water that was in the container.
  • Describe where you see the color in the celery. How did the color get there?
  • Talk about how the water feeds the plants through the stalk – follow the path.
  • What did the different colors do? The same thing, or different?
  • How do roots help plants to get water and nutrients?

Explore, Extend & Integrate

  • You can try this lesson with a white carnation, large white daisies, or even large Chinese cabbage leaves. 
  • Try cutting one flower stem lengthwise halfway up the stalk. Place half of the stem in a cup with red water and the other half of the stem in a cup with blue water. Observe what happens to the flower’s petals.

Check for Children’s Understanding

  • Do the children understand that the water feeds the plant?
  • Were the children able to describe where the color is in the celery stalk?
  • Could the children explain where the water traveled in the celery stalk?


Did You Know?

Plants need water to live and grow. Typically, when plants are watered, water is poured into the soil because the roots of the plant are in the soil. The roots contain tiny tubes called xylem. The xylem pulls the water up from the roots like a straw. Then the water moves up through these tiny tubes and out to the leaves of the plant. The plant leaves already have water in them. This water evaporates very slowly, causing room for new water to move in. This process is called transpiration.

Since it is hard to see how plants take up water and use the water to grow, we used celery to demonstrate water traveling up the plant. Although the celery’s roots have been cut off, the tiny tubes are clearly visible in the celery stalks. Using colored water makes it easier for the children to see how the water travels up through the plant and out to the leaves. 

Vocabulary: Child-Friendly Definitions

  • plant – a living thing that has leaves, makes its own food, and has roots that usually grow in the earth.
  • celery – a plant with crisp, pale green stalks that are eaten as a vegetable. Celery leaves and seeds are used as seasoning.
  • stalk – a plant's main stem.
  • absorb – to take in liquid through the surface.
  • root – the part of the plant that grows underground. Roots take in water and food, and they hold the plant in the soil.
  • food coloring – something used to give color to food and that is safe to eat.

Lesson Tips

  • It is best to present this lesson before the Rooting for Plants lesson so the children understand how plants absorb water.
  • Use fresh celery stalks and make a new cut across the bottom of the stalk prior to placing it in the colored water. Celery stalks can be rather top heavy, so you will need to use sturdy containers that don’t tip over easily.
  • Using a variety of plants, and a variety of colors, makes for some great analysis!


  • Green and Growing by Susan Blackaby
  • Jack’s Garden by Henry Cole
  • What Do Plants Need? by Josephine Selwyn

Home School Resources

Home educators: use these printable lesson PDFs to teach this lesson to your home schoolers. They're available in English and Spanish.

Home/School Connections

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Content Provided By

Common Core State Standards Initiative – These lessons are aligned with the Common Core State Standards ("CCSS"). The CCSS provide a consistent, clear understanding of the concepts and skills children are expected to learn and guide teachers to provide their students with opportunities to gain these important skills and foundational knowledge [1]. Visit the CCSS