Loose-leaf lettuce. It germinates quickly, grows well in a single jar, doesn’t need much space, and gives children something to harvest within a school term. Basil is a good second choice in a warm, bright room.
Why Lettuce
- Fast, visible growth that keeps students interested
- Happy at normal classroom temperatures
- Grows to harvest on a single fill of solution
- Students can pick and taste the leaves (wash them first)
Basil
Basil smells great and children like rubbing the leaves. It wants more warmth and light than lettuce, so use the sunniest window or a grow light.
Plants to Avoid
- Tomatoes, peppers and cucumbers: too slow and too thirsty for a jar.
- Root vegetables: carrots and radishes don’t suit the net cup setup.
- Anything inedible or toxic: keep it simple and safe.
Start From Seed or Seedlings?
Seeds let students watch germination, but add time. If the term is short, start seeds a couple of weeks ahead so the jars go out with small plants.
Related guide: running a Kratky classroom project.
