Bulb vs Seed: Two Ways to Start a Plant, in 3D
A tulip bulb and a bean seed both hold food to start a new plant, but they are very different. A bulb is a short underground stem wrapped in fleshy leaves, and the plant it grows is a copy of its parent. A seed comes from a flower and holds a brand-new baby plant with a mix of two parents.
Bulb vs seed at a glance
| Bulb | Seed | |
|---|---|---|
| What it is | A short stem surrounded by fleshy leaf bases | A baby plant with a food store inside a coat |
| Made by | The plant itself, underground | A flower, after pollination |
| New plant is | A copy of the parent | A new mix of two parents |
| Food store | Fleshy scales | Seed leaves or a separate store |
| Comes back each year | Yes, the same bulb regrows | No, each seed grows once |
| Examples | Tulip, daffodil, onion, garlic, lily | Bean, sunflower seed, acorn, apple pip |
Inside a bulb
Cut an onion in half and you can see the structure of a bulb: a flat base, called the basal plate, with roots underneath, and layer upon layer of fleshy leaves wrapped around a bud. After flowering, a tulip uses its leaves to refill the bulb and often grows small new bulbs beside it, called offsets.
Inside a seed
Split a bean open and you will find the tiny plant: a root, a shoot and two big seed leaves full of food. When the seed takes in water it swells, splits its coat and sends out the root first, then the shoot. Because it comes from pollination, each seed is slightly different, which helps plants adapt.
Quick facts
- Tulips can also be grown from seed, but it takes several years before they flower.
- Onions and garlic are bulbs we eat.
- Potatoes are tubers, not bulbs: swollen underground stems with no fleshy leaves.
- A seed can stay dormant for years and still grow.
- Bulbs are a way of cloning, called vegetative reproduction.
Look inside both
Bulb vs seed questions
What is the difference between a bulb and a seed?
A bulb is an underground stem with fleshy leaves that grows a copy of its parent. A seed comes from a flower and holds a new baby plant from two parents.
Is a tulip bulb a seed?
No. A tulip bulb is a food-storing underground stem. Tulips also make seeds in their flowers.
Is an onion a bulb?
Yes. The layers of an onion are fleshy leaf bases.
Do bulbs come back every year?
Many do. After flowering, the leaves refill the bulb with food for next year.
What is inside a bean seed?
A tiny root and shoot, two seed leaves packed with food, and a protective seed coat.
More face-offs: see all 3D comparisons.
The 3D Plant Anatomy simulator is made by Julian Neagu, a solo founder in London, as part of VisionVix Simulators. It is free to use in the browser on desktop and phone, with no sign-up.