Learning Objectives: To be able to explain and demonstrate how plants move molecules dissolved in water through the process of transpiration.
It’s Spring! In places where there are distinct seasons, this signifies overcoming the dormancy of winter…a time of growth.
In honor of Spring, you can create unique rainbow or multi-colored flowers by using just a few items: a white or light-colored carnation or rose, food dyes, a scalpel or sharp knife, water, and narrow containers or cups.
Plants designated as “vascular” have tiny tubes running along their stems called phloem and xylem. Sugars travel mostly along the phloem, while water and other small minerals travel along the xylem. These tubes are critical to the movement of vital substances throughout the plant.
You may wonder how water moves from the roots to the top of a very tall tree. A force created by the process of transpiration, the loss of water from the plant by evaporation, drives such movement. Water loss creates tension which pulls additional water molecules (and other dissolved substances) that adhere to the tubes and stick to one another, up the plant against the force of gravity.
In this activity, you will create a multi-colored flower using these principles. Cut the long stem of the flower into 4 parts longitudinally about 4 – 5 inches from the end, keeping the rest of the plant intact. Place each of these stem quarters in individual cups filled with different food dyes that are dissolved in water.
It is best if the cups and containers are long and narrow and the flower can stay upright (see video).
Allow the flower to sit several hours to days for optimal results. Note: some dyes may have more difficulty moving up the plant, so try several combinations.
You created an awesome Spring flower!