I have read that a cut end of a celery stalk can be used to "regenerate" a new one. I'm bored lately, so when I was washing and cutting up celery I decided to give it a whirl. You simply put the cut end into a container of water on the window sill and wait. Here's the result after 2 weeks... And here it is after 4 weeks, transplanted into soil. I gave it a light fertilizer and keep the soil moist since it came from growing in water. I put it into a "mottled shade with afternoon sun" location to acclimate it to being outdoors. (Photobombing ducky. ) So we'll see how this goes. I'm also going to do some green onions; once you use the green tops you can put the root end into a glass of water and they will grow more tops.
Today I have a few spring onions with the green tops trimmed off, sitting in a juice glass of water on my window sill. I'll see how the regeneration of onion tops progresses now that my celery is established.
I saw once on TV that, as an experiment, a tree from a nursery was planted upside down with the root ball up in the air where the leaves should have been, and it grew producing leaves from the root ball. I personally have seen where a low hanging tree branch was bent to the ground by someone years ago, and rooted itself and grew. Life!
I haven’t done celery, but I do my green onions usually. they seem to make smaller and smaller tops each time I trim them, but it does give me several “crops” of green onions. I have also done this with romaine lettuce, and it grows back, just very small leaves at first. It is an interesting thing to do with something that we would normally toss in the compost pile.
Well, I'm not seeing any evidence of a new stalk forming, but the celery has made a pretty pot plant and I suppose I could cut a few leaves to use as seasoning. One year I rooted an avocado tree in a water glass and eventually transplanted it into the yard. It grew to almost my height before being killed by a frost one winter.