Celeriac

About Celeriac

Celeriac, also called celery root, is a kind of celery grown for its knobby, round base instead of its stalks. The cream-colored flesh tastes like mild celery, and the roots keep for months in cold storage, which makes it a handy winter vegetable. It needs a long, cool season and steady moisture.

Grown as an annual in every zone; it needs a long, cool season. About 10 days of nights below 40F with days below 50F can make young plants bolt.

When to plant

Timing is counted from your average last spring frost (and first fall frost). Sow & Tell works out the actual dates for your ZIP code.

• Start seeds indoors: 10 to 12 weeks before the last frost
• Set out plants: up to 2 weeks after the last frost

Days count from transplanting: Arkansas lists 100 to 115 days for common varieties, and a Maine trial dug roots 121 days after setting out. Start the tiny seed indoors 10 to 12 weeks before transplanting (it can take up to 3 weeks to sprout) and set plants out after the last frost with the crown at soil level.

Soil

Fertile, well-drained loam kept evenly moist; celery-type crops need 1 to 2 inches of water a week.

Follow a soil test, aim for pH 5.8 to 6.5 in well-drained loam, and work in compost before planting.

Feeding

• 4 to 6 weeks after transplanting: nitrogen fertilizer such as 21-0-0. Side-dress beside the row and water it in; for celery, Utah State uses about 1/4 cup of 21-0-0 per 10 ft of row.
• about 3 to 4 weeks before harvest: nitrogen fertilizer such as 21-0-0. Side-dress once more beside the row and water it in.

Don't let plants dry out or overfeed them: drought, overwatering and too much fertilizer are tied to blackheart, a calcium disorder.

Harvest

Dig roots when they are about 3 to 4 inches across, from late summer into fall; the flavor is best after the first fall frost. Under a straw or leaf mulch, roots can stay in the bed and be dug through winter.

Dig each root once it is 3 to 4 inches across, from late summer into fall. You can snip a few leaves any time, and under mulch the roots can wait in the bed through winter.

Varieties (6)

Extension sources document 6 celeriac varieties.

Pests to watch for

Aphids, Thrips, Flea beetles, Tarnished plant bug, Leafhoppers, Cutworms, Cabbage looper, Twospotted spider mite

Diseases and problems

Cercospora early blight, Septoria late blight, Blackheart (calcium disorder), Powdery mildew

In the kitchen

Peeled and grated or cut into thin strips for salads, or cooked in soups and stews, pureed, and baked in gratins with other root vegetables.

Keeping it: Trim the tops to about an inch and cut off the rootlets, then keep roots near 32F with high humidity, in a perforated bag in the refrigerator or packed in damp sand; stored this way they can last six to eight months.

Safety: People with celery allergy may also react to celeriac; in Europe, celeriac allergy is often tied to mugwort and birch pollen allergy (PLoS ONE, 2011).

Pets: Not listed by the ASPCA