Gardening for Kids Science Project

Posted by Sally Odum Jul 14, 2006

"Do plants use water?

Fill jars with water and add food coloring. Place a celery stalk or white daisy and stem in the jar. As transpiration* takes place, water is pulled through the stem. The colored water will color the celery stalk or daisy petals.

Another way to discover that plants use water is to split a white carnation stem into two equal parts with a knife, from bottom up to the flower. Put each stem piece in a separate jar containing different colored water. You'll get a bicolored flower."

Courtesy of Colorado University Cooperative Extension

*Transpiration is a process caused by the evaporation of water from leaves of plants and its corresponding uptake from roots in the soil. Transpiration cools plants down and enables mass flow of minerals to where it is needed in the plant. Mass flow is caused by the decrease in hydrostatic (water) pressure in the upper parts of the plants due to the diffusion of water out of stomata into the atmosphere. Water is absorbed at the roots by osmosis, and any dissolved solutes travel with it through the xylem. (Source: Wikipedia.org)