The Science Behind Keeping Flowers Fresh
Cheery, colorful flowers make most everyone smile—and the blooming beauties smell lovely to boot! When you cut a flower to put into a vase, it'll eventually wilt, even with water and sunshine. But is there a trick to keeping flowers fresh longer?
In this experiment, you'll test pairs of flowers with different variables to learn the best way to keep cut blossoms fresh.
What can you do to keep flowers fresh longer?
- 6 flowers
- 6 small flower containers or vases
- Measuring spoon
- Sticky labels
- Put one flower in each container.
- Fill all the containers with enough water to reach right below the flowers' leaves.
- Using the marker, write "Flower 1" on a label, then stick it on your first flower container.
- Using the marker, write "Flower 2: Cut" on a label, then stick it on your second flower container.
- Cut the end of your Flower 2 in a slant, and put it back in the second container.
- Write "Flower 3: Sugar 1" on another label, then stick it on your third container.
- Measure 1 teaspoon of sugar and add it to your third container.
- Write "Flower 4: Sugar 3" on another label, then stick it on your fourth container.
- Measure 3 teaspoons of sugar and add it to your fourth container.
- Write "Flower 5: Bleach 1" on another label, then stick it on your fifth container.
- With the help of an adult, measure 1 teaspoon of bleach and add it to your fifth container.
- Write "Flower 6: Bleach 3" on another label, then stick it on your sixth container.
- Measure 3 teaspoons of bleach and add it to your sixth container.
- Place all six plants next to each other, in a sunny area.
- Think about how you grow. What do you need to grow strong and healthy? What do plants need to stay alive? Write down your notes in your notebook.
- Using your thoughts from Step 15, make a guess about whether Flower 1 or Flower 2 will stay fresh longer, including why you think your guess is correct. Write down this guess—called a hypothesis—in your notebook.
- Repeat Step 16, comparing Flower 3 and Flower 4, as well as Flower 5 and Flower 6.
- Check on your flowers every day, writing any observations (what you see) in your notebook. You can also draw what you see.
- When a flower has withered up, write down how many days it lasted in your notebook. Do this until all of the flowers have died.
For each pair of flowers, one should have lasted longer. Flower 2, with the slanted cut, should have lived longer than Flower 1. Flowers 3 and 4, with the sugar, will vary in how long they stayed fresh, but Flower 3 should have lived longer than Flower 4. The flower with a small amount of bleach, Flower 5, should have lived longer than Flower 6.
Flowers live by absorbing nutrients from the soil and making sugar through photosynthesis. Photosynthesis is the process that happens when a plant's leaves absorb sunlight, and turn it into energy that the plant can use. By putting a plant into water, you are taking away a large amount of nutrients the roots, leaves and stem get from soil. Cutting the stem in a slant—instead of straight across—will allow it to absorb water better.
Both sugar and bleach help flowers stay fresh. Sugar gives them nutrients they need that aren't found in water, while bleach keeps the water clean and kills bacteria that causes flowers to wilt faster. However, too much of each can cause the flower to die faster than if you didn't add anything to the water. You used a small container in the experiment, which is why the flowers with one teaspoon of sugar and bleach should have lived longer than the flowers with three teaspoons of each.
You may have guessed that the results of this experiment will be different for different kinds of flowers. Using what you've learned from this experiment, keep the science going by switching up the variables of this project. What would happen if you used a different flower? How about if you tried a different sized container with different amounts of sugar and bleach? There are many ways in keeping flowers fresh longer, try experimenting with different things, and maybe you'll discover other secrets!
Warning is hereby given that not all Project Ideas are appropriate for all individuals or in all circumstances. Implementation of any Science Project Idea should be undertaken only in appropriate settings and with appropriate parental or other supervision. Reading and following the safety precautions of all materials used in a project is the sole responsibility of each individual. For further information, consult your state’s handbook of Science Safety.