No need to get rid of those table scraps so quickly—here is a fun planting activity any young child can enjoy. No seeds are required for this experiment. All you need are vegetable scraps, and in a few short days, they will regrow into a new plant.
- One bunch of green onions or similar vegetable
- Small container of water
- Ruler *For younger learners, substitute a ruler for a small, easy-to-hold item like quarters or Lego blocks. A week’s worth of growth can be measured effectively both in inches or quarters lined up along the plant.
For this activity, keep the small white roots and the first 2 inches of thick white or light green plant growth. Cut most of the length of the long green leaves off and set aside. Don’t let it go to waste though. What meal will you make? The mild onion can be sliced thinly and sprinkled into almost anything.
Record the measurement of the onion along with your starting date. Place upright in a small container of water so the roots and bottom of the cutting are submerged and the cut portion is above water. Select a location that receives some sunlight, like a windowsill or countertop.
Make a prediction: How tall do you think your green onion plant will grow in three days? In a week?
Visit your onion plant every day. Remove your plant from the jar, dry it off and lay it flat to measure height. Be sure to measure from the same point every day. Return the plant to its jar and refresh its water occasionally. Record your findings and notable milestones. How does your original prediction for plant growth compare to your measured results?
When you are finished with the experiment, rinse and cut the leaves to use again to create a meal. Congratulations, you have just gotten twice the food from one purchase and contributed to sustainability of our environment! Getting the most out of the food you bring home is a simple step to help the planet.
Extension: For an extra math boost, plot the onion growth on a chart with time (in days) on the x-axis and height (in inches or quarters, etc.) on the y-axis. What shape does the growth show if you connect the data points? A line or a curve? What can this tell you about the rate of growth throughout the experiment?