Children are curious beings. And there is no better place than nature and your garden for them to disconnect from technology and have hands-on learning experiences.
A garden is more than the plants you see; it’s also many things you cannot see—such as bacteria, chemical reactions, and water vapor. In fact, the interconnectedness of a garden can inspire all sorts of scientific explorations for children of all ages.
Outdoor Happens is reader-supported. When you buy through links on our site, we may earn an affiliate commission. Click to learn more
Follow your curiosity, step out into the garden and nature, and give these science experiments a try.
Preschool Science Projects in Nature
Budding young scientists need to know how to master the art of observation.
For young children, a sensory garden is a great way to explore the world around them and engage their senses.
When designing a sensory garden, you want to account for all five senses.
- Sight: Consider the variety of colors, types, and sizes of plants. What colors are present? What shapes?
- Touch: How does the fuzzy texture of lamb’s ear compare with the smooth leaves of a bean plant? How about dandelion fluff?
- Sound: Bamboo, corn or ornamental grasses make enticing whispering sounds when the wind blows. Bee-friendly favorites (like borage or bachelor’s buttons) will encourage the buzzing of bees in your garden.
- Smell: Herbs such as rosemary and lavender are delightfully fragrant.
- Taste: In a vegetable garden, taste is the best the sense to explore! Nothing compares to the sweetness of homegrown peas or the complexity of a garden-fresh carrots.
Flower Dyeing Experiment
All living things need water, and plants are no exception.
This can be observed by conducting a simple experiment.
- Pick a few flowers. (White or pale flowers are best)
- Put each flower in its own glass of water.
- Put several drops of food coloring into each glass.
- Observe what happens to the flower.
A plant uses its stem to transport water up to the leaves and flowers. Because the water is dyed, you can observe as the water travels through the plant.
The water will be used by the plant to perform an important process called photosynthesis.
Older children might conduct this experiment and consider the implications of what they’re seeing. In this case, harmless food dye was added.
What happens when the water we use in our gardens becomes contaminated with substances more harmful than food coloring?
Herbalism for Kids is a wonderful 4-week journey into herbalism for kids of all ages. It's chock-full of engaging, hands-on educational activities and fun, designed to spark their curiosity and interest in the wild world of plants.
Week 3 is my favorite - Have Fun in the Kitchen! This lesson is packed full of kid-friendly herbal recipes and treats - how about some herb ice cream, yummy popsicles, or Flower Power Jigglers? Then, we'll make some herbal playdough!
Sign up a single camper or your entire family!
School Age Science Experiments in the Garden
Germination refers to the moment when a seed breaks dormancy and begins its life as a plant.
Each seed has enough energy within it to sprout a pair of “seedling leaves” and a root. This process does not require soil or sunlight. Only water is needed.
Different types of plants need different amounts of time to germinate. Vegetables like peas and beans can germinate in just a few days while hot peppers and some flowers can take a few weeks!
Choose a variety of seeds, label them, and place them between soaked pieces of paper towel.
Child scientists can record how long it takes for the plant to emerge from the seed and observe the differences in shape and size.
This is a great resource on how to conduct a germination experiment, which includes an observation journal.
One of my favorite ways to study the germination process is while growing sprouts. I love that you can not only watch the process unfold before your eyes but that you can eat the result too!
The Water Cycle
Gardens need rain, but where does rain come from? The answer can be found in the water cycle and its four stages: evaporation, condensation, precipitation, and collection.
This simple experiment allows you to make a mini water cycle in a bowl using some household items: Create a Mini Water Cycle by The Water Project.
There are several ways in which the garden is affected by the water cycle. Precipitation is the obvious one, but evaporation is another. Gardeners, in particular, want to prevent evaporation so that they don’t have to water as often.
One way for children to see evidence of evaporation taking place is to try the following experiment on a sunny day:
- Fill two cups full of soil.
- Wet both cups of soil with one cup of water.
- Place a one-inch layer of straw or lawn trimmings on top of one of the cups.
- Place the cups out into the direct sunlight.
- Check back in a few hours later. Which cup has moister soil?
This experiment demonstrates how evaporation pulls water out of the soil and how something as simple as a little mulch can prevent this from happening.
Everyone knows that gardens are about growing, but not everyone thinks about how much decomposition is also present in the garden. Plants are always shedding old leaves.
When we consume food, there are often parts that we don’t eat, like the hearts of peppers and the corn cobs.
Enter decomposition. Bacteria break these materials down over time to produce nutrient-rich matter that feeds future plants.
Composting can be a time-consuming process that takes several months, but with a few modifications and some slicing and dicing, the process can be accelerated to a few weeks.
Here’s one example of how this can be done in something as simple as a sandwich bag.
Or older children might like to tackle building a bigger system using 2-L soft bottles.
Advanced Science Experiments in the Garden
Citizen Seed Trials
I recently participated in a citizen seed trial, and I think that everyone should have this opportunity.
Here’s how it works.
A group of gardeners volunteers to collect data on the growth of two or three varieties of a certain vegetable, in my case, it was two varieties of peas.
The seeds are mailed to the participant (often for free), and then the citizen scientist completes a growth record that includes information about germination rate, growth rate, disease resistance, yield, flavor, and other factors.
In the end, it is compared with the data other people collected and you can see how your experience compared to others. Sometimes other gardeners are on the other side of the continent!
This kind of project requires youth to put their scientific observation skills to work in the real world.
Photosynthesis is the process by which plants transform light and water into glucose and oxygen.
This process not only allows a plant to feed itself (with glucose), but also provides an important source of oxygen for creatures like us to breathe.
The following experiment uses a sample of an aquatic plant (these are often sold in the aquarium section of pet stores for a few dollars or online from Amazon), baking soda, and some other household items.
These are used to set up a scenario where you can watch a plant produce oxygen and see how the amount of light the plant is exposed to affects how much oxygen is produced.
This experiment is ideal for youth who are in high school and already have some understanding of scientific methods.
Gardens are more than just a place to grow food. For all ages, they are a place to spark curiosity and learn new things.
What lessons will you learn on your next visit to the garden?