Red Cabbage pH Experiment

My family recently visited one of our favorite science museums, and my kids got to do a very cool hands-on experiment with red cabbage that I couldn't wait to tell you about. After my last time writing about red cabbage (the time I accidentally made fart paint), I thought this was a good way to redeem one of my favorite vegetables.

This experiment would be fun to do with kids of any age. My 4-year old has no idea what pH means, but it didn't stop her from having fun using a medicine dropper. So, if your kid has the dexterity to work a dropper, they would likely enjoy it.

Here's the basic gist:

  • Cut up about 1/4 red cabbage, and boil it in a few cups of water. Pull out the cabbage and reserve the cabbage water. Let it cool and pour into a container. It will be purple.
  • Gather a few things from your house that are acidic, basic, or neutral. (Within reason, don't choose anything unsafe!) Here are a few ideas: aspirin, baking soda, detergent powder, lemon juice, vinegar, ammonia, sugar, salt. Write the name of each substance down on a piece of paper.
  • Have kids scoop a small amount (like, 1/4 - 1/2 teaspoon) of each of the gathered substances into small bowls or ramekins. A plastic paint tray would work really well. Make sure you label which substance is which!
  • Using a medicine dropper or pipette, put a dropper-full of cabbage water on the substance. What color does it turn? Record the color results on your paper listing all the substances you are trying.
  • Interpret your results. If it stays the same (purple), your substance is pH neutral. If it turns pink, it's an acid. If it turns blue, it's a base. The stronger the color, the higher (or lower) the pH of the substance.

As I said, we did this experiment at a museum, but it would be a great hands-on activity for studying pH, or to use up some questionable cabbage. This activity is also mentioned in GrowLab: Activities, along with more discussion on plant acids, and the effects of acid rain. Check it out if you want to dive deeper on pH!



The Magic of Greenhouses


Greenhouses bring back fond childhood memories for me.  I can remember going with my Dad to water at the University greenhouses on weekends and loving the humidity, warmth and just the way they smelled.  The lush, green growth was a welcome sight especially when the world outdoors was dormant in winter months. Visiting Franklin Park Conservatory was also a Christmas tradition for our family and no matter how many times we visited, seeing bananas grow on trees was just so awesome!

With these experience etched in my brain, I can definitely relate to the appeal of creating year round growing spaces at schools that can be achieved through the installation of a greenhouse.  They can extend your growing season significantly and be especially useful for schools in northern climates. That being said, I am usually not quick to recommend them for most schools.  I have lost count of how many times I have gotten a call from a teacher explaining they took a job at a new school and inherited an abandoned greenhouse with no clue what to do with it.  Even more than regular outdoor school garden beds, when a school greenhouse loses its main champion, it seems like sustaining the program becomes a real challenge.  Although it is certainly not brain surgery, greenhouses definitely require more knowledge and maintenance than many garden spaces (and usually more expenses too).

I am very excited to have found a new resource to share with educators in search of support for new and revitalized greenhouse programs. The United States Botanic Garden, the National Center for Appropriate Technology, and City Blossoms have collaborated to publish a great a new Greenhouse Manual specifically for educators.  You can download it for free!

It walks you through the steps of getting started, provides a review of different types of greenhouses, offers basic growing instructions, suggests tips for trouble shooting problems and includes a plethora of ides for connecting it to the curriculum – a key component to making sure it is sustainable over time.  Throughout the guide they also offer program spotlights so you can read about real life programs in action.

So whether you are considering investing in a brand new school greenhouse or you fall into the category of needing to refurbish an existing greenhouse, make sure to check out this very informative Greenhouse Manual.  A big thanks to our friends at United States Botanic Garden, the National Center for Appropriate Technology, and City Blossoms for creating this much needed resource!

Indoor Garden-Based Activities to Get You Through the Winter

winter activities

It’s the middle of the winter and for folks in northern climates the gardening season can’t feel further away. Even if you can’t get outside during this cold and snowy season, there are plenty of garden-based activities that you can try out indoors. Below are five fun indoor options to try out with your students:

  1. Grow Salad Greens for a taste test: Greens are perhaps the most simple and straightforward indoor growing option. They grow well under lights or simply on sunny windowsills (though definitely be aware of how chilly it can be close to a window). Try planting different varieties of greens (leaf lettuce, kale, arugula, mustard greens) so that you can compare the appearance, flavor and texture of each.
  2. Create a  Vermicomposting System: Worm composting is remarkably fun, easy, and smell free (if you do it right). Vermicomposting systems are great for learning about decomposition and sustainability—observing worms can be fascinating and you get a nutrient rich by-product that you can add to garden beds or potted plants. You can also buy pre-made systems if you’d rather not make your own (I have one of these at home and love it)!
  3. Try your hand at Kitchen Scrap Gardening: Turning food scraps into new plants is magical, whether you’re using avocado pits, sweet potatoes, or beheaded pineapples. Pro tip: I’ve had great success tossing avocado pits in my vermicomposting system, letting them sprout there, then replanting them in soil—one pit has grown into a 5 ft tall plant!
  4. Design your own Hydroponic System: While they might seem complex at first glance, hydroponic systems can easily be created in a classroom using an assortment of repurposed items. Follow the steps in the linked activity or learn from one of our Carton to Garden contest winners who made a hydroponic system out of milk cartons from their school cafeteria.
  5. Make Seed Paper: This is a fairly involved (and often messy) project, but it yields incredible results. I’ve done this a handful of times with my students and they’re always enthralled by the paper making process and extremely excited about the prospect of planting their own piece of seed paper in the garden come spring.