You will need:
- leafy celery. This was actually hard to find, since it seems that most grocery celeries have the leaves cut off--my theory is that the leaves begin to spoil before the stalks, and so impedes the celery's shelf life. Next spring, we may try to grown our own leafy celery for science experiments.
- liquid food coloring. For cooking and baking, I use professional-quality food coloring gel or paste, but liquid food coloring is often the best for crafting.
- clear glass. We used a Mason jar.
2. Fill the glass jar 1/3 to 1/2 full of water, and dye it a dark color with several drops of food coloring. Blue and purple and even a dark red work well:
As the celery stalk sits in the water, it acts like any plant, in that it draws water up into its leaves. Because this water is colored, very gradually, over the course of several hours, you will begin to notice spots of color in the leaves as the colored water reaches it. Over time, these spots of color will become larger and more numerous:
And now you may add to your mental picture of what our messy living room table looks like, a jar of celery sitting in colored water, for this experiment apparently often bears repeating.