Cut the root end of the bunch of celery 2-4 inches from the bottom. Place it in a small bowl. Add a small amount of water so that the root end has about 1/4th inch of water.
After there are roots, you can plant the celery in a pot or in the garden. When the plant is established you can trim a stalk or two at a time from the outside edges. It will continue to regrow.
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