When you think of the desert, what comes to mind? You might think of a dry, dusty landscape. Long stretches of barren sand may also come to mind. Of course, there’s probably one other image that’s likely to pop into your brain. What are we talking about? The cactus, of course!

Any movie or cartoon ever set in the desert always features the cactus. Often, it’s pictured as a tall, green, prickly plant that manages to survive the desert heat without water. However, there are actually over 2,000 different types of cacti (that’s what you call more than one cactus) in the world.

Some cacti are tall, green, and prickly like the ones you may have seen in movies or cartoons. Those are often a specific type of cactus called the saguaro cactus. Many cacti, though, are much smaller and come in a variety of colors and shapes.

Cacti are native to the Americas and can be found from the southern tip of South America to western Canada in North America. They usually live in areas that are relatively dry. Many cacti thrive in areas that are extremely dry, such as the Atacama Desert — one of the driest places on Earth.

Like all living things, cacti need water to survive. Given the areas where they live, though, water is often scarce. To compensate, cacti have developed special abilities that allow them to conserve the water they do receive and make it last a long time.

For example, the prickly spines of cacti are actually highly-modified leaves. Spines protect cacti from animals that eat plants and also help to reduce water loss by restricting air flow near the cactus.

Most cacti have extensive, but shallow root systems that allow them to soak up any rainfall that may come their way. Specialized stems allow cacti to store water for a long time, since rainfall is often sporadic in the deserts that cacti call home.

For example, a fully-grown saguaro cactus can soak up and store up to 200 gallons of water during a good downpour! Many desert travelers have learned that, in an emergency, a cactus can be opened to find life-saving fluids.

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    • Great question, Tyler! People go looking for saguaro cactus fruits in very hot climates. These fruits are SUPER sweet and are hard to come by, but they do exist. Have you tried saguaro cacti fruit before? :)

  1. Wow, what an artistic view of Saguaro Park, quite an excellent video!!! Love the music too. What is the name of the background tune?

    • Hey there Sue, thank you for sharing your comment with us today! We’re so excited that you enjoyed our Wonder video– a very talented man by the name of Tom Guilmette made the video. He did a great job– the video makes us feel like we are right there! We’re sorry we cannot answer your specific questions, but we hope you continue to Wonder about cool places in nature with us! :)

    • That’s WONDERful to hear, Destiny! We Wonder if you have traveled to a place where cactus live? We are always keeping our eyes and ears open for the Wonders all around us, and we hope you do, too! :)

    • We hope you’ll do some WONDERing of your own to find the answer to that, Jimmyrock! It doesn’t happen often, and some people plan their farming season around it! We can’t wait to learn more about what you find! :)

  2. Hi,
    Our class has a few questions for you!
    1. How does the cactus grow if people don’t plant it?
    2. How do you open a cactus and get a drink?
    3. How does a cactus grow its spikes?
    4. Does a cactus have other liquid inside it other than water?
    5. Do you use the spikes to open the cactus?
    6. How do the flowers grow on the cactus?

    We look forward to reading your answers.

    Thank you so much :)

    • What spectacular questions from our Wonder Friends, Gr. 1’s at Evergreen School! We’re so excited that you’re here today! Happy Tuesday! :)

      Cacti are lots of fun to Wonder about, aren’t they? We are over-the-moon to read your questions and Wonders about cactus plants. Your imaginations have been hard at work – great job! We hope you’ll do some WONDERing of your own to find out about these spiky plants; you can Wonder with the help of your school librarian, your teacher, and the Internet, too! :)

      Cacti do have water in them, but if you’re out in the desert, we wouldn’t recommend you slice one open. The water may not taste like the tap water you drink every day– it could taste bitter and acidic (and not so refreshing)! YIKES!

      Some cactus leaves are eaten– there are lots of ways to prepare them. Instead of cauliflower, some recipes include cactus leaves! Hmmm… we Wonder what they taste like?!

      We can’t wait to hear about what you learn from your Wonder exploration, friends! :)

  3. There must be something inside the cactus plant telling the cactus water is short supply, and we need to conserve water. On the same token, there must be something in the plant telling the cactus there is plenty of water after a rain, renourish your self with water and get ready for another dry spell.

    What is inside the cactus that is telling the cactus what to do when it is dry, and the cactus needs to conserve water?

    Likewise what is inside the cactus telling the cactus there is plenty of water, and the cactus should store water for the next dry spell?

    • Great WONDERing, Albert Link! You can research more about cactus’ at your library. Always keep WONDERing and thanks for commenting! :)

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Have you ever wondered…

  • How does a cactus live without water?
  • How many types of cacti are there?
  • Could you live in the desert?

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Try It Out

We hope today’s Wonder of the Day left you thirsty for more. Keep the learning going by exploring one or more of the following activities with a friend or family member:

  • How important is water to your survival? More importantly, how critical is water to maintaining good health? Learn more about how much water your body needs and why when you check out a previous Wonder of the Day: How Much Water Do You Need To Survive?
  • Did you realize that cacti came in so many shapes, sizes, and colors? Explore the wide variety of cacti around the world by checking out the Cactuspedia Photo Gallery! Which cacti are your favorites? Why? If you could grow any cactus at home, which one would you choose?
  • How would you survive if you lived in a desert? We’re sure some of our Wonder Friends do live in desert areas. Those of you who live in or near a desert, post a picture or leave us a comment on Facebook to let us know what life in the desert is like. If you don’t live in or near a desert, what do you think life would be like in the desert? How would the desert differ from where you live now? Would you like the dry weather? Do you think it would be too hot? If you lived in a desert, would you want to have a cactus in your yard? Why or why not? Could you imagine playing hide and seek in a desert full of cacti? Ouch! That could be a prickly game!

Still Wondering

The Desert Biome video segment from NOVA: “A Desert Place” describes the physical characteristics and organisms that define the desert biome.

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