Growing your own celery indoors is easy from a bunch you get at the grocery store. Cut the stalks from the base of the plant about an inch from the bottom. Place the base in a shallow container of warm water and place on a sunny windowsill.
After a few days there will be new leaves growing from the center of the base. In about a week or so, plant the celery base in a container with potting soil. Cover the base completely with soil except for the new leaf tips in the center and water generously .
In a month or so celery stalks will begin to emerge from the center.
Repot into a larger planting container or directly into your garden, weather permitting. Harvest stalks as often as you like leaving the root in the soil. Stalks will continue to grow from the center.