About a week ago I had some really bad celery, it wasn’t crispy and it started to turn yellow. I cut off all the yellow parts, (they went to compost) and used the middle, better parts for a soup. I was left with just the bottom part and decided to do little experiment. In a small shallow bowl I put some cold water and put the celery piece in, I also added carrot tops. Its seating on my kitchen counter where is warmer then on the window and I have a LED light above my sink so I leave it on. Now week later new celery is growing and even the carrots are growing, next will be parsnip for some fresh parsley.