How to Grow Celery Hearts

Fill the cells of a seed-starting tray with potting soil. Sow one seed into each tray at a depth of 1/8 inch and water until the soil settles. Place the trays in a warm, sunny spot. Do this 12 weeks before the average date of the last frost in your area.

Transplant the seedlings to 4-inch plant pots filled with potting soil when they are 1 inch tall. Keep these pots in a sunny, warm spot.

Prepare the planting several weeks before the last frost. The site should be cool and exposed to full sun. The soil should be moist but not waterlogged and have a pH of 5.8 to 6.8. Cover the site with 4 inches of compost and turn it into the soil at a depth of 12 inches with a tiller.

Transplant the celery seedlings to the prepared garden bed two weeks before last frost. Space them 6 to 10 inches apart. Space the rows 24 inches apart. Water until the soil settles.

Cover the soil with a 2-inch layer of mulch. Water frequently enough to keep the soil constantly moist, or the hearts will be stringy along with the rest of the stalks.

Apply 1/2 tbsp. of nitrogen fertilizer to the soil around every four plants. Repeat the fertilization once a week. For organic gardens, side-dress the celery with compost during the middle of the season.

Harvest the celery when the whole head is 2 to 3 inches wide so the hearts will be tender. Cut the celery off just below the soil line.