demonstrations:color_changing_flowers

Color Changing Flowers

Materials: ★☆☆ Easy to get from supermarket or hardware store
Difficulty: ★☆☆ Can be easily done by most teenagers
Safety: ★☆☆ Minimal safety procedures required

Categories: Plants

Alternative titles: Bicoloured Flowers

Summary

This experiment shows how cut flowers absorb water through their stems. By splitting the stem and placing each half into different colored water, flowers can be dyed in two colors, demonstrating capillary action and water transport in plants.

Procedure

  1. Fill separate glasses with water and add different food coloring to each.
  2. Trim the stems of white flowers such as daisies, gerberas, or carnations.
  3. Carefully split each stem lengthwise down the middle so that it has two “legs”.
  4. Place each leg of the stem into a different colored glass of water.
  5. Leave the flowers for a day or more, observing how the petals take on two distinct colors.

Color Changing Flowers Experiment - Part 2 - Dr Boyd The Chemist:


📄 Bicoloured Flowers - Go Science Kids: https://www.gosciencekids.com/index.html%3Fp=1036.html

Variations

  • Try different types of flowers such as carnations, daisies, or roses.
  • Use three or more colors by splitting the stem into additional sections.
  • Test whether warmer water, sugar water, or vinegar affects the uptake of color.
  • Try fluorescent dyes or tonic water under UV light for glowing flowers.

Safety Precautions

  • Adults should handle sharp knives or scissors when cutting stems.
  • Food coloring can stain clothes and hands.

Questions to Consider

  • How does water travel up the flower stem? (Through xylem tubes via capillary action.)
  • Why don’t the colors mix inside the flower? (Different xylem pathways carry water to different petal regions.)
  • What would happen if you placed the flower in plain water after it had absorbed color? (The color may fade as plain water dilutes the pigment in the petals.)
  • Do thicker or thinner stems absorb color more effectively? (Thinner stems often show results more quickly because water moves faster.)