In North America, commercial production of celery is dominated by the varieties called Pascal celery.[7] Gardeners can grow a range of cultivars, many of which differ little from the wild species, mainly in having stouter leaf stems. They are ranged under two classes, white and red; the white cultivars being generally the best flavoured, and the most crisp and tender. The stalks grow in tight, straight, parallel bunches, and are typically marketed fresh that way, without roots and just a little green leaf remaining.The plants are raised from seed, sown either in a hot bed or in the open garden according to the season of the year, and after one or two thinnings and transplantings, they are, on attaining a height of 15–20 cm, planted out in deep trenches for convenience of blanching, which is effected by earthing up to exclude light from the stems.
In temperate countries, celery is also grown for its seeds. Actually very small fruit, these "seeds" yield a valuable volatile oil used in the perfume and pharmaceutical industries. They also contain an organic compound called apiol. Celery seeds can be used as flavouring or spice, either as whole seeds or ground and mixed with salt, as celery salt.




