Vegetables & garden · Allium cepa
Discovering bulb onions
Puschel holds a dry onion skin on his paw. Puschel“A jacket that will never fit me.”
The short answer
An onion's juicy layers are thickened leaf parts storing reserves around a very short stem. Roots grow underneath. The bulb is not a fruit.
See the connection
Simplified drawings, not to scale. Not a guide for identifying species.
An imagined Wusel scene
Puschel and Flauschi investigate
Puschel holds a dry onion skin on his paw. Puschel“A jacket that will never fit me.”
Flauschi turns a harvested bulb onion so they can both see the little roots underneath. Its papery skin rustles softly.
Flauschi“It belongs to the onion,” she says. Puschel puts his tiny jacket in the bowl for plant scraps. An adult will prepare the onion later.
Discover
A bulb onion is a storage organ made of a very short stem and fleshy leaf parts. Its juicy layers are not a fruit.
Understand
The outer layers can become dry and papery. Thin roots grow from the basal plate underneath.
Connections
Bulb onions can be grown from seeds or small onion sets. Sets are already young bulbs, not seeds.
Try explaining it
What forms an onion’s juicy layers?
Choose a), b) or c), then explain your choice.
- a)Many separate seeds.
- b)Fruits stacked together.
- c)Thickened leaf parts.
Show the explanation
Correct: c): Thickened leaf parts.
The thickened leaf parts store reserves. The short stem and roots are underneath.
Word help
- cell
- A tiny living unit. Living things are made of cells.
Explore in more detail
Here you will find longer explanations and further details. You can explore them together.
Why does an onion have so many layers?
The juicy layers are swollen, fleshy leaf parts attached to a very short stem called the basal plate. They store reserves. Roots grow below and green leaves can sprout above. An onion bulb is therefore neither a fruit nor simply a single thick root.
Compare and understand
Cutting damages cells, bringing substances together that produce an irritating volatile compound. It can make eyes water. Volatile means it passes readily into the air. Adults handle cutting; examine a prepared half without holding it near your face.
An optional question for further exploration
You can use the longer explanation above. This is extra, not needed for the first quiz.
An extra question
Is an onion set an especially large seed?
Show answer
No. It is a small bulb that has already grown. Bulb onions can also be grown from seeds.