When you cut the stalks of celery off, don't throw the bottoms away. Place the bottoms of the celery in a shallow plate of water. Check the celery bottoms every day or two. Spritz the tops of the celery and make sure there is a enough water to cover the bottom of the plate and maybe just a bit more. After about a week you will start to see new stalks of celery emerge. At that time you will plant them in a pot or the ground. Planting the bottoms up to the new growth. I haven't planted mine yet, mostly because I need to find a place to put them but I will be doing it in the next few days.
I figure if I do this enough, between dehydrating and re-growing I'll never have to buy celery again.
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