Category: Fun Science Activity (Page 94 of 112)

Weekend Science Fun: What We Can Learn From Weeds

Wherever and whenever you plant a garden, you have to expect some “plants out of place” or weeds to follow. Before you rip them out, remember weeds aren’t always just nuisances. Spend some time getting to know weeds and you might find they have something to offer.

Weed Activities with Children

1.    Plant identification

One of the first things young children need to learn when they grow a garden is how to identify the various vegetables, flowers and weeds. I’m sure we all have heard family stories about the time the beets got weeded out and the dandelions were left behind. Identifying tiny seedlings is no mean feat, and so learning to observe and identify plant characteristics is key.

Start pointing out things like leaf color, shape, the presence of hairs on the stems, etc. Did you know the name for dandelion comes from “teeth of the lion” and refers to the jagged teeth on the leaf margin? A simple fact like that might help a child remember what a dandelion looks like. Let some of the weeds go to flower so you can see what the entire plant cycle looks like. (Try not to let it spread seeds though).

dandelion

Save some samples of plants from the garden by pressing them. A leaf press is a useful piece of equipment for studying plants, and also for pressing flowers for crafts. An old telephone book can be a handy substitute if you don’t have a press. Or if you are handy, you can make one like this:

 

Identify the plants you find by looking in plant books or online for identification guides. Don’t be afraid to ask for expert help. Many counties have Master Gardener programs. The Master Gardeners are volunteers who help answer gardening questions for the public.

2.    How do weeds measure up to vegetables and flowers?

Compare growth rates of various plants, including weeds by measuring the height of the plants at weekly intervals with a yardstick or tape measure. Take pictures. How many inches does the weed grow versus the garden plant? Which one emerges from the ground first? Which one is ready to flower first? Do you think the weeds might shade the vegetables or compete with them for food and water? Why or why not?

3. Are weeds useful at all?

A weed is basically a plant out of place. If it was growing somewhere besides your garden, it might have some uses. How might a weed be useful?

I think most people have heard of eating dandelion greens. In fact, I saw some dandelion greens at the store the other day for $4.99 a pound. What about garlic mustard? The Brooklyn Botanical Garden has this article Garlic Mustard—A Palatable Pest about how to identify the weed and suggestions for preparing it.

My maternal grandmother studied botany. She often ate plants others considered to be weeds, because she knew how to accurately identify plants and knew which ones were edible at which stages. Just remember, certain weeds are poisonous, so learn from an expert before trying to eat anything new.

Notice whether any wildlife in the area feeds on the plants your think of as weeds. My dad was going to mow a patch of common milkweeds last summer but I showed him how insects feed on the leaves. I heard reports that later in the summer he was proudly showing the neighbors all the beautiful butterflies visiting “his” milkweed patch.

As long as they aren’t introduced/invasive species, many so-called weeds are really wildflowers in disguise.

sowthistle

Weekend Science Fun: Germination Science Experiments

Did you try the germination tests from last week? Did you get anything that looks like this?

bean radicle

If you enjoyed sprouting seeds, then here are a few more ideas for seed germination science experiments.

Before starting, however, let’s take a minute and think about how information from experiments on seeds and germination might be important. Last week we discussed how you could use a germination test to see if old seed you have lying around is still viable (able to make new plants). Plant scientists interested in maintaining rare plants, entrusted with ensuring maximum yields from crop plants and/or concerned with storing seeds in seed banks for the future study the changes in seeds over time and how to slow or prevent loss of viability. These scientists subject seeds to different conditions and examine the physical and chemical changes that occur as time passes. Their findings indicate that factors such as temperature, moisture, diseases, and chemical pollutants can all change seed viability.

Experiment 1. Effect of temperature on seeds and seed germination

Think of ways to test whether temperature effects seed sprouting or percent germination.

Example A:
Choose seeds of one kind of plant to test. (Note: Be sure to check the seed package carefully. Some seeds are treated with pesticides). Randomly assign the seeds to three categories. With the help of an adult, place 1/3 of the seeds on a paper towel or on a microwave safe plate and heat in a microwave on high for thirty seconds. Allow seeds, especially oily ones, to cool before touching them.  Add 1/3 of the seeds in a freezer overnight in a freezer. Leave the remaining seeds at room temperature. Then perform a germination test as described last week. Count the number of seeds that germinated for each treatment and divide by the total of seeds (for that treatment) to obtain the percent germinated. If there are no differences, how can you modify this test?

Example B:
Choose seeds of one kind of plant and divide into three groups. Prepare each group for germination as discussed last week. Place one group in the fridge, one at room temperature and one in a sunny window or other place warmer than room temperature. Make sure they all stay moist but not too wet. Record the number of days until germination and also the percent germination (see Example B.)

Experiment 2. Rate of germination of seeds from different plants
Collect seeds from different plants (two examples of plants with vastly different germination times are radishes and carrots.) Perform the germination test as described last week.

Note:  because radishes and carrots have different germination times, it is possible to plant them together in a garden. The radishes will come up and mature first. The slower carrots will benefit from the extra room left behind as the radishes are pulled out and used.

Experiment 3. Effect of chemicals or pollutants on seed germination

Use your imagination to come up with treatments that may increase or decrease germination. Think about things like salts (may be present in the water or soil), nutrients, and/or antimicrobial treatments that might change how many seeds of a given batch germinate.

As always, we would love to hear your ideas and/or results.

tomato seed sprouting

For further study:
Seeds and Plants (Science Workbook) by Diane O’Hanesian, John Jones (Illustrator)
Grades 2-3

This book does a good job with terminology and also showing concrete, real world examples. Better done than many science books for the younger set.


The Magic School Bus Plants Seeds: A Book About How Living Things Grow by Joanna Cole (Author), John Speirs (Illustrator), Bruce Degan (Illustrator)


For many more suggestions, visit our list of children’s books about seeds at Science Books for Kids.

childrens-books-about-seeds

And a treat for adults interested in science and plants:
Seed to Seed: The Secret Life of Plants by Nicholas Harberd


Disclosures: I am an affiliate for Amazon. If you click through the linked titles or ads and make a purchase, I will receive a small commission at no extra charge to you. Proceeds will be used to maintain this self-hosted blog.

Weekend Science Fun: Planning A Children’s Garden

A  garden can be a wonderful learning experience. By giving your child the freedom to design his or her own space, a budget to work with and a few simple tools, you can have a project that builds a lifetime of skills and memories.

Planning a children’s garden can be done any time of year, but right now is a great time to get started.

What do you need?

Gardening is relatively simple. You need:

  • Spot with at least 6 to 8 hours of full sun per day
  • Soil
  • Water
  • Seeds and/or transplants

Of those three, the sunlight hours are often the most difficult to find. Because of the Earth’s tilt, the position of the sun changes with the seasons. Make sure the spot you have chosen isn’t shaded by trees, walls, or buildings throughout the day.

As for soil, you must decide if you are going to put the seeds or transplants into the ground, grow them in a container, or create a raised bed.  Containers must be at least 8 inches in diameter.

Also, find out the growing season for your location.  Check with local gardening organizations or your local Cooperative Extension office for planting dates.

Types of Gardens

Help your child decide on the type of garden he or she would like to plant. Does your child like vegetables? Then a kitchen garden would be perfect. Other types of gardens might be flower gardens or herb gardens. You might want to check our previous posts on theme gardens for ideas.

Beyond Planning

If you have had gardens in the past and want to expand your learning experiences even more, now is the time to plan garden activities, too.  These days there are a number of websites and organizations devoted to gardening with children and often they have free curricula.

Your local Cooperative Extension office is likely to have information about gardening with children. For example, the University of Illinois Extension has a Planning My Garden area for kids with information on how to grow different plants just a click away. PBS has information/ideas about gardening with children and KidsGardening.org has a wonderful gardening activities.

If you want to be part of an organization, take a look at the Cooperative Extension’s Junior Master Gardener Program. They have curricula for sale.

Budgeting for Seeds

The next step for planning is to develop a seed budget and order seeds.

Here are some links to seed company websites. Most are still willing to send a paper copy of their catalogs, if you want one. These are a  few that came to mind, no endorsement is implied. Note:  Many of these websites also have a wealth of information about gardening.

Botanical Interests

Burpee

Gurney’s Seed and Nursery Company

Johnny’s Seeds

Park Seed Co.

Seeds of Change

Seed Saver’s Exchange

 

Please let us know if you have any questions.

 

bean seed

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