You know green-stemmed celery (Apium graveolens) well, but you may not be aware that some celery cultivars deliver both attractive stem colors and varied flavors. Still other varieties of produce leaves and roots that are as flavorful as their stems. A member of the carrot family, celery is an annual herb and a marsh plant that likes plentiful moisture and cool weather.
The variety of celery you're probably most familiar with is the variety grown for its edible stems (Apium graveloens var. dulce). Stem celery grows in dense clumps of ribbed stalks that readily absorb moisture from the soil and become rigid and crisp. "Ventura" is a cultivar with large, upright green stems. Red varieties, such as "Redventure," have red stems and a rich, nutty flavor. "Pascal Giant" is an heirloom variety that produces thick golden stems up to 2 feet tall.
Celery stems have the best flavor when they are blanched so the stalks are nearly white. The traditional method of blanching stalks is to mound soil around them as they grow, but some self-blanching cultivars lighten naturally on their own. The stems of these varieties eventually attain a light golden color rather than the deep green of standard varieties, and they have a milder flavor than that of darker stems. Self-blanching celery cultivars include "Golden Boy," "Tango" and "Golden Self-Blanching."
Root and Leaf Varieties
Root celery (Apium graveolens var. rapaceum), commonly called celeriac, is grown for its edible root rather than for its stems. Leaf varieties of celery (Apium graveolens var. secalinum) produce neither thick stems nor large edible roots. The flavor of celeriac is much like that of stem celery, and it can be eaten either raw or cooked, while leaf celery is used to flavor soup stocks.
All varieties of celery need plenty of water, and they grow best in organically rich soil that is moist to the point of being wet. They also like full sun, but they are sensitive to heat and prefer cool weather. All celery can tolerate light frost, and celeriac root in particular develops its best flavor after it has been exposed to a few frosts. Most stem varieties, too, should be harvested in the fall, after a frost but before the stems become dry and stringy.