Kohlrabi for Kids | Plant Facts, Life Cycle & Activities

What vegetable looks like a round ball with leaves sticking out around it? Meet kohlrabi! Its unusual appearance offers a fascinating way to investigate stems, leaves, roots, and the different plant structures people harvest for food.

Explore kohlrabi facts, discover why its rounded portion is a stem, and follow the plant’s life cycle. Then continue learning with research worksheets, Montessori cards, reading activities, and matching printables.

🌿 What Is Kohlrabi?

Kohlrabi belongs to the species Brassica oleracea, usually identified as the Kohlrabi or Gongylodes Group. It is part of the mustard family, Brassicaceae.

Cabbage, broccoli, cauliflower, and many types of kale belong to the same species. These cultivated forms have been selected for different features.

Kohlrabi is especially recognizable for its swollen stem. Although it may resemble a turnip, the rounded portion develops above the soil rather than being an enlarged root.

Begin with the Kohlrabi Research Activity. Invite children to record what they already know and write one question they would like to investigate.

🔍 A Swollen Stem Above the Ground

The rounded part commonly harvested from kohlrabi is an enlarged stem. Leaf stalks attach around this structure, while the roots extend below it into the soil.

People sometimes call the rounded portion a “bulb,” but it is not a true bulb like an onion. Using “swollen stem” makes its botanical identity clearer.

Swollen stem: The enlarged aboveground structure commonly harvested for food.
Leaf blade: The broad, flat portion of a leaf.
Petiole: The leaf stalk connecting the blade to the stem.
Roots: Structures that anchor the plant and absorb water and nutrients.
Growing point: The region where new shoot growth develops.

Draw a whole plant with a soil line. Place the swollen stem above that line and the roots below it. Use arrows to show where the leaves attach.

🎨 Green and Purple Kohlrabi

Kohlrabi varieties can have pale green or purple outer surfaces. Their appearance depends on the variety, so purple is not a compulsory stage that follows green.

Use labeled photographs to compare examples. Observe the swollen stem’s outline, the positions of the leaves, and the color of the outside.

An adult-prepared cut section or clear photograph can reveal the pale interior. Compare this view with the outside without assuming that outer color describes every internal tissue.

Create two drawings with the captions “Outside view” and “Cut section.” Explain which features become visible only after cutting.

🌱 Kohlrabi Life Cycle

Kohlrabi is generally biennial, although it is usually grown as a one-season vegetable crop. Its food-harvest stage comes before flowering and mature seed production.

Follow this simplified seed-to-seed sequence:

Seed: A mature seed contains the beginning of a new kohlrabi plant.
Germination: With suitable moisture, temperature, and air, a root and shoot emerge.
Seedling: The young plant opens its seed leaves and develops true leaves.
Vegetative growth: Roots and leaves grow while a section of the stem enlarges above the soil.
Flowering transition: After suitable development and environmental conditions, a flowering stalk grows.
Flowering: The plant produces flowers that can undergo pollination and fertilization.
Pod and seed development: Seed-bearing pods develop, and mature seeds can potentially begin another generation.

The reproductive sequence can extend beyond the usual harvest season. An enlarged edible stem is not a fruit containing the plant’s seeds.

Use the Kohlrabi Life Cycle Poster and Cut-and-Paste Activity to practice sequencing and explain the changes between stages.

🕒 Harvest Stage and Reproductive Maturity

Kohlrabi is commonly harvested while its swollen stem is tender. This is a vegetative stage, meaning the crop can be ready for food before producing flowers.

A kohlrabi ready for the kitchen is therefore at a different stage from a plant grown to provide mature seeds.

Create two notebook headings: “Swollen stem for food” and “Flowers and pods for seeds.” Add drawings showing the structures involved in each purpose.

This comparison helps children understand that “ready to harvest” depends on what people want from a plant. Harvest time does not always mark the completion of its reproductive life cycle.

🌼 Where Do Kohlrabi Seeds Form?

Kohlrabi seeds develop in pods after flowering and successful fertilization. They do not form inside the rounded edible stem.

The pods are botanical fruits. This means a plant grown for its stem can still produce fruits later, even though those fruits are not the main food crop.

Compare labeled photographs of a swollen stem, a flowering plant, and seed pods. Ask children to identify each structure and explain its role.

Complete two sentences: “The part commonly harvested for food is…” and “The seeds develop inside….” Encourage learners to use the words “stem” and “pods.”

🥬 Different Forms of the Same Species

Kohlrabi and cabbage illustrate how cultivated plants from the same species can look very different. Kohlrabi is selected for an enlarged stem, while heading cabbage forms a dense arrangement of leaves.

Compare whole-plant photographs rather than prepared food pieces alone. Identify which structures have become especially prominent in each form.

A shared species name does not mean the plants must look identical. Cultivated forms can have different shapes and uses.

Make a comparison chart with headings for “Visible leaves,” “Main harvested structure,” and “Growth form.” Support each entry with a labeled reference.

📏 Observe Growth Carefully

If a growing plant is available, record changes in the swollen stem over time. Measure its width using the same method and position each time.

Distinguish stem width from total plant height. Include the date and measurement unit so observations can be compared meaningfully.

If using photographs, choose images with a scale reference. A larger image on a page does not necessarily show a larger specimen.

Ask children to describe evidence-based changes such as “The stem measured wider” rather than assigning every plant a fixed growth rate.

🧩 Kohlrabi Learning Activities

Match and name: Use the Kohlrabi Life Cycle Montessori 3-Part Cards to practice matching and plant vocabulary.
Draw and label: Sketch a whole plant with its swollen stem above the soil and roots below.
Compare structures: Explain how a swollen stem differs from a root, a true bulb, and a seed pod.
Sequence and retell: Arrange growth-stage pictures and distinguish food harvest from seed production.
Read for evidence: Explore the Kohlrabi Reading Comprehension Activity Pack and find information that supports an answer.
Match visual details: Use the Kohlrabi Cut and Match Activity and explain the clues behind each match.

For a connected study, explore the Kohlrabi 3-in-1 Real Image Bundle. Choose one learning goal per session, such as recognizing stages, practicing vocabulary, or organizing research.

❓ Kohlrabi Questions for Kids

Is the round part of kohlrabi a root?
No. It is a swollen stem that grows just above the soil surface.

Is kohlrabi a true bulb like an onion?
No. Although it is sometimes called a bulb in everyday language, its rounded structure is an enlarged stem.

Are green and purple kohlrabi different growth stages?
Not necessarily. These colors occur in different varieties and are not a compulsory color-changing sequence.

Where do kohlrabi seeds develop?
Seeds develop inside pods after flowering and successful fertilization, not inside the swollen stem.