Bulbs are an amazing, self-containing unit that is both seed and all of the nutrients the plant will need to start growing. Because bulbs are underground and often in a climate where they start growing under snow or frozen ground, these extra nutrients are especially important. They have adapted for survival in a harsh environment.In most areas, this lesson is best done in the fall before the ground has frozen.
This lesson was loosely based on a bulb botany lesson at kidsgardening.com (a fantastic resource).
Objective
- Learn about what plants need to grow and how bulbs are a little different from seeds.
- Learn about the different parts of a bulb (including which is the top and the bottom).
- Plant a bulb!
What you need
- a bulb for each child to plant (I chose freesia because they will bloom while the kids are in school). You can buy a bag of 25 freesia bulbs on Amazon or you can go to your local garden store to pick them up.
- garden journal to sketch bulb inside (the teacher and kids made these)
- pencil (for sketching)
- Onions and garlic cut in two to be passed around to look at the inside of a bulb. If possible, get an onion that has started to grow a little shoot
Extra Bonus for Inside the Classroom
- three paperwhite or amaryllis bulbs
- clear vase
- rocks
Bulb Lesson or What to teach the kids about bulbs
Start off by asking what plants need (answer key: water, sun, soil, and nutrients). Explain that while many plants get their nutrients from the soil around them through roots, bulbs have their nutrients stored within. It is a self-contained flower factory. Within the bulb, is nearly everything the flower needs to come to life!
Show the inside of the bulb. I brought several cut onions and explain the different parts of the bulbs (see hand out). I have them sketch the different layers in their journals.
One thing not on the handout is about how they multiply. This is a great article to read on getting bulbs to multiply. Essentially, show the kids the little nubs on the side of the bulb. They kind of resemble pups and are like the bulbs booty. As the leaves gather energy from the sun, they will direct it into producing new bulbs from these bulb booties.
Then I teach them how to plan their bulb. You place the stem down and I have them demonstrate. Each bulb requires a different depth so please read your package. A good rule of thumb though is to plant the bulb twice as deep as it is tall. We planted in loose dirt so I had the kids shimmy each bulb down until it was low enough. We divided a square garden bed into four sections for four different classes to plant. We labeled each section with how many bulbs we planted, what kind, and the date.
The kids recorded in their journal how many bulbs were planted. Each month we go back and check the progress, counting how many have come up, how many have flowered and
I gave each teacher forced paperwihites for the classroom to see the progress of the roots because flowers inside are fun too!
Follow up lessons
What I have loved so much about the bulbs is that we can revisit them every month. We have counted how many plants have sprout up in each and how many of those have flowered. The kids record the information in their garden journals. I don’t write down the numbers, but rely on them keeping good records. We often end up counting 3 or 4 times and then we take the number that we get most. I talk about how they do this in science too because if you only measure or count once, you can often end up with a mistake.
Then I ask why there are more bulbs growing in one section than another when we planted the exact same number? They have very good guesses and of course, I don’t know why the answer is, but I like that they are thinking in the garden about outcomes and how all of this is not an exact science. This is one of my favorite parts of every lesson, when the kids ask good questions!
