Fall may be the time for pumpkin spice, but as the temperatures continue to drop, peppermint becomes the flavor of winter. Red and white striped candy canes adorning steaming mugs of hot chocolate, crushed peppermint candies sprinkled on top of freshly baked cookies - peppermint is everywhere! So imagine my surprise when I saw what looked like peppermint striped ribbon candy under my Foldscope 2.0!

Figure 1. Picture of flower petal viewed under a Foldscope 2.0 at 50X magnification

(Photo Credit: Holly A. Stuart)

How Did Peppermint Get In My Foldscope?

Well, the answer is that there wasn’t any peppermint candy under my Foldscope. I was studying capillary action in plant vascular systems (capillary action occurs when liquid from below gets pulled up against gravity). This is how plants are able to pull water up from the ground to reach stems, branches, leaves, and flowers. It is a phenomenon that you can observe by putting white flowers in a vase of colored water.

Figure 2. Picture of breath flowers in red colored water

(Photo Credit: Holly A. Stuart)

Watching Plants Drink

The colored water is easy to trace as it travels up the stem and out to the leaves and flower petals. Over time, the white petals begin to get more and more red due to the colored water moving through the plant.

Figure 3. Picture of breath flowers that had turned red from the colored water

(Photo Credit: Holly A. Stuart)

Vascular Bundles In The Flower Petals

Vascular bundles are a series of tube shaped structures (think of a group of straws) that work together to distribute water, minerals, and sugars throughout the plant. These bundles are not only located in the stem of the plant, they also extend out to the leaves and flower petals. The bundles are easy to see when the water they are transporting is red. Those red lines on the white flower petals are the vascular bundles.

Figure 4. Picture of red vascular bundles in the white flower viewed under a Foldscope 2.0 at 50X magnification

(Photo Credit: Holly A. Stuart)

It is interesting to note that the closer you look at the vascular bundles, the less stark they appear against the white flower cells. At 50X magnification, it looks like the lines are very distinct. However, when you increase the magnification to 140X you can see that while the lines themselves are darker, the surrounding plant cells have become infused with the red dye. This shows the permeability of the cell walls - water is able to flow from cell to cell carrying the red dye with it.

Figure 5. Picture of red vascular bundles in the white flower viewed under a Foldscope 2.0 at 50X magnification (left) and 140X magnification (right)

(Photo Credit: Holly A. Stuart)

Of course, now I have so many questions about this phenomenon! How do the vascular bundle patterns vary from flower to flower? How long would it take for the petal to turn completely red? What are the variables that could impact that time? It is amazing how one observation can instigate a multitude of future scientific investigations!

Have you looked at the vascular bundles of flower petals under a Foldscope 2.0? Use your Foldscope to dive into the microscopic world and find the beauty that is there waiting for you. Share your microscopic images and thoughts on the Microcosmos. Be sure to tag us on social media when you post the results of your explorations, creations, and discoveries! We love to see how Foldscopers around the world are using their Foldscopes in new and innovative ways!

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