Gardening Articles: Edibles :: Herbs
by National Gardening Association Editors
Celery has a reputation for being a fussy, hard-to-grow vegetable. There's a lot of truth to that, but with the right climate and some care, you can grow large, tender plants. A dozen plants will take up five or six feet of row, and it's worth trying.
A Long Season Crop
Celery is challenging because it needs a long time to grow - up to 130 or 140 days of mostly cool weather - and it's quite demanding when it comes to water and fertilizer. 'Utah 52-70R Improved' is a good, well-adapted variety. If your soil stays moist and has plenty of organic matter in it, you're in good shape for growing celery. Shut off the water supply even for a short time, however, and you're in trouble.
The roots of celery plants are limited, usually stretching just six to eight inches away from the plant and only two to three inches deep, so the top part of the soil not only has to have enough moisture, it must also contain all the nutrients the plants need.
Keep Celery Cool
Celery plants don't like hot weather at all. The crop will thrive only where the winters are mild, or where the summers are relatively cool, or where there's a long, cool growing period in the fall.
Because celery takes such a long time to grow, in most parts of the country it's best to start the seeds in plant boxes or flats indoors to get a jump on the season. Celery seeds are slow to germinate, so soak them overnight to speed up the process. Plant them indoors 10 to 12 weeks before the last frost. When the plants are two inches tall, transplant them to individual peat pots or to another, deeper, flat with new potting soil. If you use flats, put the plants at least two inches apart.
Transplant celery to the garden as early as a week or two before the last frost date. Plants should be four to six inches high when you set them out. Be sure to harden plants off first for a week to 10 days to get them used to spring weather. It the weather turns cold after you set your celery out (night temperatures consistently under 55° F for about two weeks), the plants may go to seed prematurely. But because of the need for a long growing season, it's often worth the gamble to set at least some plants out early.
To transplant celery, first work the soil, mixing in the fertilizer (about one pound of 5-10-10 per 30 square feet). Remove some of the outside leaves from each plant before setting them in. As with head lettuce, this trimming helps the roots recover from the transplant shock and resume normal growth more quickly.
Space the plants about eight inches apart, setting them a little deeper than they were growing in the flat. Mulch the plants after they're about six inches tall to help keep the soil moist and roots cool. It will also help to keep down weeds, which is important because celery grows slowly and doesn't appreciate any competition from weeds. If you don't mulch, be careful not to weed too deeply near plants. Celery has a shallow root system that can be harmed by deep cultivation.