I read multiple times online that if you cut off the bottom couple inches of a bunch of celery and place it in some water, it will start to grow and you will shortly have your own celery plant. I decided to give it a try.
Low and behold, within a few days, I started to see growth in the middle of the plant. I added a few more celery stalks to my collection after I saw it actually worked.
I also tried this with romaine lettuce and got the same result.
After a few weeks, the plants were large enough to plant outside in the veggie bed. I dug a hole large enough to cover the old stalk and only had the new growth above ground, then watered thoroughly. I then waited patiently to see how much more the plants would grow.
Unfortunately, they never did grow large enough for me to harvest any more celery. I think part of the challenge might have been that I did this in winter, so I'll have to try it again in the spring to see if I get a different result.