Set the celery in a shallow glass bowl or jar. Fill with enough water to submerge an inch of the root end. Place the bowl or jar where it can get good natural.
Choose a large container with good drainage holes. As a rough guide, for smaller shrubs which grow up to 3ft, use pots with a 14 – 16 inch diameter. For larger.
Lower the pH of the potting soil. I've read that pumpkins will grow in anything from 5.5 to 7.5 but I have yet to find any real consensus on a more narrow range.