Topsy's experiments
A cress heart
Plants and trees thrive almost everywhere around the world. Let’s find out together what they need to grow besides water.
What you’ll need
What you’ll need
- Cress seeds
- Soil
- A shallow, wide bowl
- A piece of cardboard large enough to cover the entire bowl
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- A felt-tipped pen
- Scissors
- Packaging tape
- Water
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How to do it
How to do it
1. Fill the bowl half full with soil.
2. Spread the cress seeds evenly and generously over the entire surface. Press the seeds down firmly and pour water over them, preferably with a small watering can.
3. Draw a heart on the cardboard.
4. Cut out the heart using the scissors. This will be easier if you first poke a hole in the center. Let an adult help you do this. Then place the cardboard over the bowl.
5. Use the packaging tape to tape the cardboard firmly to the bowl. Place the bowl on a windowsill. Now you have to wait for up to two weeks! Watch what happens carefully.
6. After a few days, the cress seeds will start sprouting. After one to two weeks, the cress will already have grown considerably. Now remove the cardboard. You've grown some cress in the shape of a heart! The cress only grew where the soil wasn't covered by the cardboard.
Pay attention to the following
Pay attention to the following
The soil must always be a little moist and evenly exposed to sunlight. Only allow light to enter through the heart-shaped opening.
What's the secret?
What's the secret?
Only the cress exposed to sunlight grew beautiful, green and succulent. Plants need sunlight to grow and thrive.
Why is that? Just like people, plants need food to grow. They take water from the earth and carbon dioxide from the air to make sugar with the help of solar energy. This process is called photosynthesis.