It is very easy to let a piece of celery take root in a shallow dish of water and then grown it in hydroponics.
Use the bottom, after having used the celery for cooking, stripped of all its branches.
First allow it to root in a shallow dish of water:
The water needs to be changed daily to prevent rot.
New roots begin to form within a few days.
After 2-3 weeks, new celery stalks are formed and the root system is well developed. You can now plant it in clay pebbles and add a nutrient solution for hydroponics:
Normally, you should be able to use the new branches in the kitchen but mine has made 1 big blooming stalk and some smaller branches that do not seem to grow very much. I will not be making soup anytime soon 🙂