Do you know how flowers grow? During springtime, you’ve probably seen tiny green plants start to peek up above the ground. Soon some of those plants will grow beautiful flowers! Discover the miracle of plants with the science projects and other fun things to do in this issue.
How Flowers Grow Science Projects
Watch Seeds Sprout
What You Need:
What You Do:
- Fill the cup about 3/4 full with potting soil.
- Push a seed along the side of the cup into soil. Cover the hole with soil. You should be able to see the seed from the outside of the cup, but not the top. Repeat all around the cup, leaving a little room to grow in between each seed.
- Water the soil. It should be moist, but the water should soak in and not stay on top of the soil.
- Set your cup in a windowsill or another warm, sunny spot. Turn the cup every few days to make sure all of the seeds get sunlight.
- Look at your seeds every day and water them whenever the soil looks dry.
When you gave the seeds the right conditions, you saw how flowers grow within only a few days! What conditions did you provide for your seeds? You gave them soil, water, sunlight, and warmth. A plant needs all of those conditions in order to grow.
You can probably see tiny roots growing from your seeds down into the soil. Plants use roots to get water and nutrients from the soil. You should also be able to see a small green stem sprouting up above the soil. This stem will continue to grow from the nutrients and water it gets from the roots. The plant will eventually grow leaves. Leaves use sunlight to make and store more food for the plant to use as it keeps growing. Soon your little plants will be too big for the plastic cup. Ask an adult to help you find a place outside or in a large pot where you can plant them and continue to watch them grow.
After awhile, the plants will grow little buds that will bloom into flowers. The flowers will eventually turn into a fruit; in this case, they will grow into bean pods! Inside of these fruits is where more seeds are formed for the next batch of plants to grow from. If the flowers of a plant don’t grow into a fruit, the seeds are formed inside the flower instead.
Mini Flower Garden
This project has two parts: In the first part you’ll plant flower seeds in an egg carton and watch them sprout into plants. In the second part, you will experiment to see what happens if your plants don’t get enough water or sunlight. Ask an adult to help you do this project!
What You Need:
- an empty cardboard egg carton (not Styrofoam or plastic!)
- plastic wrap
- potting soil
- flower seeds (look for seeds that grow quickly)
- sunny windowsill or other warm place
- a marker
- 3 sheets of black construction paper
- masking tape (or any tape that isn’t clear)
- worksheet chart
What You Do, Part 1:
- Open the egg carton and carefully cut the top and bottom halves apart. Line the lid with a piece of plastic wrap to make a tray. Set the bottom half (the part with the 12 little sections) of the carton into the tray you just made.
- Fill each section about 3/4 of the way full of potting soil.
- Have an adult help you read the back of the package of your flower seeds to find out how deep to plant them. Poke three or four little holes in the soil in one section using your pinky finger. Make the holes as deep as the package says to plant the seeds. Put one seed into each hole, then cover the seeds with a little more soil.
- Repeat step four in each section of your garden so that each one has 3-4 seeds planted.
- Sprinkle some water into each section to water the seeds. Don’t add too much – just make sure the soil looks a little bit wet.
- Carefully move your whole garden to a warm place that gets a lot of sunlight, like a windowsill.
- Look at the soil in each section every day. Do you see any signs that your seeds are growing? If the soil looks dry, add some water. If it still feels moist, check it again tomorrow.
- Once all of the plants have grown at least 2 inches tall, you can begin Part 2 of the experiment.
What You Do, Part 2:
Start this part of the experiment in the morning so that you can check on your plants after a whole day of sunlight. Use this worksheet to keep track of your garden during your experiments!
- Draw a line down the middle of the carton (the short way) so that there are six sections on each side of the line. Draw a star on one side of the carton. The six sections between the star and the line are the ones you will experiment with. Let’s call this the test half. The other half of the garden will be called the control half, because you will not change anything about how you take care of the plants in that half.
- Draw a star on the worksheet in the same place as the one on your garden. This is a chart to help you keep track of the test half.
- Choose three sections in the test half of your garden for a sunlight test. These plants will still get the same amount of water as the control plants, but they will not get any light!
- Make a cone to cover the plants: roll up a sheet of black paper into a narrow cone shape and tape the edge. Put a piece of tape over the top to block more light. Make three cones and put them over the sections you chose to test. Make sure the cones completely cover the plants.
- Mark the circles on your chart to show which sections will not get any light (cross out the sunlight and circle the water).
- The other three sections of plants in the test half are for a water test. These plants will still get the same amount of sunlight as the control plants, but they will not get any water!
- Mark the circles on your chart to show which sections you are not going to water.
- Look at your chart and water all of the sections in the garden with an equal amount of water, except for the three from step 6 that do not get water.
- Put your garden in a sunny spot and leave it there all day. After the sun sets, check on your plants. Carefully lift up the cones to check the sunless plants. If you see any changes, you can draw pictures on the worksheet. If nothing has changed, put the cones back on. In the morning, water them again, and leave them for another day. Continue to check and water them until you can see a difference between the plants. It might take several days, depending on how much sunlight they are getting and the type of flowers you are growing.
- When you are finished with the experiment, make sure you take the cones off. The plants in the test half may need some extra-special care to get back to health!
- When your plants outgrow the egg carton cups, ask an adult to help you cut the cups apart with scissors and plant each one in a pot or outside in a real garden, if you have one. Dig a hole just big enough to set the egg carton cup in. You can plant the whole cardboard cup in the soil right along with the plant; it will break down in the soil over time. Push dirt around the plant to hold it up and cover the hole. Make sure you continue to water your plants!
Part 1: For the first few days, you probably didn’t see much going on in your flower garden. After about a week, some little green stems should have begun to sprout up out of the soil in some of the cups. This is the first sign that your flower plants are growing, even though they had already been growing for some time below the soil, like you saw in the last experiment. Keep watering your young plants and you will be amazed at how quickly they will grow! Soon little leaves should start to appear on the stems.
Part 2: What did you notice about the plants that didn’t get any sunlight? Their stems and leaves probably started to look a little more yellow than the other plants. They might have wilted some or not grown as tall as the control plants. Even though these plants were getting the same amount of water as the other plants, they weren’t getting any sunlight! Water isn’t enough to keep a plant healthy. Why not? Well, plants use sunlight to create food. When they don’t get any sunlight, they can’t create food! Plants need water and food to survive!
What did you notice about the plants that received the same amount of sunlight as the control plants, but no water? Did the plants start to wilt without water, or do they just not grow as much as the others? At first you might not have noticed any difference at all, but once the soil dried out, the plants’ roots started to run out of water and the plants probably started to wilt and maybe even wither or shrivel up a little bit. Even though these plants were still getting plenty of sunlight, they still couldn’t make food, because water is one of the things required for plants to be able to make food!
How Flowers Grow Science Lessons
The Life Cycle of Plants
To allow kids to experience the life cycle of plants (or how flowers grow) up close, use this section with the ‘Watch Seeds Sprout’ science project.
Most plants start their life as some sort of seed. A seed has all of the information it needs to grow into a plant, but before it can grow, it needs certain conditions to be right. Until it is in the right conditions, the seed is dormant – it’s kind of like it is asleep. When the seed has everything that it needs to live (sunlight, air, water, and nutrients from soil), it will ‘wake up’ and sprout, or germinate. The sprouted seed will soon grow a stem above the ground. Below the ground, it will grow roots. Soon small green leaves will grow out from the stem. At the top of the stem, a flower bud might begin to form (if it is a flowering plant). Eventually the flower bud will open up, or bloom, into a flower. New seeds will grow inside of the flower. The plant uses these seeds to produce new plants. If the plant is a type that produces fruit, such as an apple tree, the flower will slowly turn into a fruit that is still connected to the stem (or a branch) of the plant. The fruit gets nutrients and everything it needs from the roots, stem, and leaves of the plant it is growing on. Now the plant’s new seeds are inside of that fruit. Eventually those new seeds will fall to the ground or be planted by a human and grow into new plants! The original plant may die right away after it completes its life cycle, or it may live for several more years.
Bees & Pollination
Flower petals are a very important part of how flowers grow. Besides smelling good, they also do a special job. They protect the parts of the flower that make seeds from weather and any harm that could be caused by animals or insects trying to eat them. The petals slowly open up as the flower blooms. Once they have opened, the petals have another job to do – they attract insects to come and drink the nectar inside the flowers.
In order for the seeds of flowers to be able to make more plants, they have to be pollinated. Most kinds of flowers rely on insects or other things in nature to do the pollinating for them. A bee is a common insect that pollinates flowers when it flies from flower to flower drinking nectar from deep inside the flower. As it rubs against the parts of the flower that contain pollen, some of the pollen usually sticks to the bee’s body. Then the bee flies off to another flower to get more nectar. Most flowers have a long tube in their middle, with a sticky spot on the top called a stigma. When the bee gets to a new flower, some of the pollen will probably fall onto the flower’s stigma and stick to it. Then the pollen slides down the tube to a place where it will help form a seed, or maybe many seeds!
Some other insects that help pollinate plants are ants, beetles, and butterflies. They are all attracted to the flowers for their nectar, but they end up carrying pollen from flower to flower in the same way that bees do.
Use this section with part two of the ‘Mini Flower Garden’ science project. This printable worksheet is used as a chart for that project.
In the first experiment, you learned that plants need certain conditions in order to grow. Do you remember what they are? Sunlight, water, and good soil with nutrients. Plants also need air. How does a plant use these things to grow? All green plants use a special process called photosynthesis to make food that they use to grow. Photosynthesis happens in the plant’s leaves. How does it happen? Well, the plant’s leaves soak up energy from sunlight. The leaves also gather a gas called carbon dioxide from the air. Inside the leaves, a very complex chemical reaction, called photosynthesis, happens between the energy from the sunlight, water from the soil, and the carbon dioxide from the air! Sugars that the plant can eat are created in the reaction. Oxygen is also released by the plant during photosynthesis, which is great for humans and other animals, since oxygen is the main gas that we breathe! Extra food that the plant doesn’t use right away is stored in the leaves for later.
Read our science lesson about Chemistry to learn more about carbon dioxide, oxygen, and chemical reactions.
How Flowers Grow Science Words
Germinate – when a seed begins to grow. Until it germinates, it is dormant, or asleep.
Dormant – something that is alive, but is temporarily not growing or having any physical activity.
Pollination – when pollen is transferred from one flower to another to form a seed.
Photosynthesis – a process that happens in the leaves of plants where sunlight, water, and carbon dioxide are converted into food and oxygen.