STEM BUDDIES

← Back to blog

Published on 21/02/2025 by James Best

The Thirsty Plant: Unlocking Nature’s Magic Straw!

Let’s Discover Something Amazing!

Have you ever seen a tall tree and wondered, “How does all that water get up there?” 🤔 Plants are pretty amazing – they can suck up water from the ground like a super straw, even reaching the top branches! But how does this magic happen? Get ready to uncover the incredible science behind capillary action!

A large tree with water droplets on the leaves

Time to Get Our Hands Dirty!

Safety First: This experiment involves food colouring, so cover your workspace and wear an apron or old clothes, just in case! Adult supervision is recommended.

Materials Needed:

  • 2 glasses or jars
  • Water
  • Food colouring (any colour)
  • Paper towels
  • Scissors

Let’s Get Started!

  1. Fill one glass about three-quarters full with water and add a few drops of food colouring. Mix well.
  2. Fold a paper towel in half lengthwise, then roll it up tightly into a cylinder.
  3. Stand the paper towel cylinder up in the empty glass and let the bottom touch the surface.
  4. Carefully pour the coloured water into the other glass until it’s about an inch deep.
  5. Watch closely as the coloured water starts climbing up the paper towel! 🧑‍🔬

What’s Happening? The narrow spaces inside the paper towel are acting like tiny straws, pulling the water upwards through capillary action! This is the same process that helps plants suck up water and nutrients from the soil. Isn’t that amazing?

Mind-Blowing Facts!

  • 🌳 The world’s tallest tree, a California redwood, is over 115 metres (379 feet) tall! Its roots can pull water all the way up from the ground using capillary action.
  • 🌵 Desert plants like cacti have extra-tiny tubes to help them soak up as much water as possible from the dry soil.
  • 📝 The ancient Egyptians used capillary action to make the first pens by soaking a hollow reed in ink!

Your Turn to Explore!

  • 🖍️ Try the paper towel experiment again, but this time, use different materials like string, fabric, or even your own hair! Which ones work best?
  • 🍅 Observe the stem of a freshly cut flower or vegetable. Can you see the tiny tubes carrying water up from the base?
  • 📐 How high can you make the coloured water climb? Experiment with different paper towel shapes and sizes!

The Big Question

Capillary action is all around us, helping plants survive and even making our pens work! But here’s something to ponder: if you zoomed in really close, would water look like tiny little trains travelling through the plant’s pipeline? 🚂 What other surprising places might you find capillary action at work? The natural world is full of wonders waiting to be explored!

Written by James Best

← Back to blog
  • Doctor Detective: How Elizabeth Blackwell Changed Medicine Forever!

    Doctor Detective: How Elizabeth Blackwell Changed Medicine Forever!

    Join us on an exciting journey to discover how Elizabeth Blackwell became the world's first female doctor! Learn how her determination changed medicine forever and try your hand at some fun doctor-inspired activities.

  • The Scientist Who Cracked the Code: Flossie Wong-Staal and the Fight Against HIV

    The Scientist Who Cracked the Code: Flossie Wong-Staal and the Fight Against HIV

    Ever wonder how scientists discovered the virus that causes AIDS? Get ready to meet the brilliant explorer who helped crack the code - and try some fun DNA experiments along the way!

  • The HIV Detective: How Françoise Cracked the Case 🕵️‍♀️

    The HIV Detective: How Françoise Cracked the Case 🕵️‍♀️

    Join brilliant scientist Françoise Barré-Sinoussi on her quest to solve one of science's biggest mysteries - the cause of AIDS! Get ready for an exciting journey into the microscopic world of viruses and the amazing immune system.

  • Brilliant Boffins: Rosalind Franklin - The DNA Detective

    Brilliant Boffins: Rosalind Franklin - The DNA Detective

    Join us on an exciting journey to discover how Rosalind Franklin used special X-ray cameras to snap pictures of the tiny building blocks of life itself!

  • Knock, Knock, No Ouch! How Woodpeckers Bash Trees Without Getting Dizzy

    Knock, Knock, No Ouch! How Woodpeckers Bash Trees Without Getting Dizzy

    Discover the incredible superpowers that let woodpeckers hammer into trees without getting headaches! Learn about nature's perfect shock absorbers and how scientists are copying woodpecker design to make better helmets and protect our brains.

  • Vaccine Superheroes: How Katalin Karikó's Tiny Messengers Save Lives!

    Vaccine Superheroes: How Katalin Karikó's Tiny Messengers Save Lives!

    Discover how a determined scientist created special messages for our bodies that help fight nasty germs! Learn how Katalin Karikó's amazing mRNA discoveries are teaching our bodies to protect themselves just like superhero training.