I almost always have a sprouting potato or two around my kitchen. I’ll buy a bag of spuds and only use part of it, leaving the rest to turn green and eventually end up in the compost.
Luckily, those orphan potatoes are perfect for a few science experiments. One teaches you a little bit about physics as you watch an object in motion (a drinking straw) remain in motion as you drive the flimsy plastic deep into a potato. The other, a potato maze, teaches you a little biology as you think about what a potato needs to grow.
We’d stabbed a straw into a potato before, but it worked shockingly well with the boiling potatoes we got from our farm share. The straws went all the way through! Click here to learn how to do the potato experiment yourself!
To make a potato maze, all you need is a sprouted potato, duct tape,some cardboard and a shoe box (or any cardboard box with a lid.) Cut out cardboard pieces the same depth as the box, tape them together, bend them and tape them inside of the box to create a maze.
Try to keep the walls of the maze the same height as the box and be sure to cut an opening at the far end of the maze so that light can get in at one end.
Put a sprouted potato or two in the maze. Close the box and seal any light leaks (other than the opening) with tape. (See photo at top for an idea of how your maze should look, but they’ll all be different and there’s no “right” way to make your maze! Just make sure there’s a direct tunnel between your potato and the opening!)
Place the box somewhere where it will get plenty of bright sunlight pouring into the opening. Wait a few weeks and check your potatoes. (You can check them more often if you’re impatient, but they won’t grow any faster.)
What happens to the potatoes?
They should grow towards the light, since plants need light to grow. Using a process called photosynthesis, they can change sunlight, carbon dioxide, water and minerals into electrical and then chemical energy, which allows them to grow into food for other living things. In the process, they also give off oxygen, the gas that we breath.
How do you your potatoes grow without food and water?
There are nutrients and water stored in potatos that allow them to start growing for a while without soil and water.
It’s been a stormy summer in Minnesota, and we’ve seen more than our fair share of tornadoes. As a kid, I was always fascinated by stories of pieces of straw from a field being driven into wooden planks in barns and houses by the swirling winds.
With a potato, plastic drinking straws and a glass of water, we were able to see for ourselves how this could happen. Like drinking straws, real straw is hollow and although a potato is much softer than a piece of wood, we got the picture. I was skeptical about the experiment, but it worked!
Just soak a potato in a glass of water for about 30 minutes. We used a red, boiling potato, because that’s what I had on hand.
Then, grasp a straw tightly, near the middle and stab it into the potato. We were surprised to find that, instead of breaking or bending, the straw can be driven quite a way into the potato. This happens because objects in motion, like the straw, tend to stay in motion and objects at rest, like the potato, tend to stay at rest. This is known as inertia. In addition, the thin edges of a drinking straw don’t offer much resistance.