You probably won’t see this knobby root with its skinny top gracing the pictures of brimming baskets of produce, but don’t let the less-than-perfect look of the vegetable fool you. It’s easier to grow than celery, has a mild celery flavor, and enjoys a long storage life. Cooks are finding this European favorite very useful in the kitchen.
Celeriac is a cool-season biennial grown as an annual. It’s best when it comes in for harvest in cool weather. It’s also known as turnip-rooted celery. Both the foliage and the root are edible.
Celeriac prefers rich soil with consistent moisture. You’ll want to work into the soil about 2 inches of compost over the area in which you’ll plant your celeriac. The ideal pH range for this root vegetable is 6.0 to 7.0. It likes full sun but will tolerate some light shade. Celeriac is a heavy feeder, so add some compost to your planting beds mid-season, and dose with a bit of compost tea or Protogrow® every two to three weeks.
When to Plant
In cooler climates, sow your seeds indoors 8 to 10 weeks before the last expected spring frost. In cool summer, short season areas, sow in early spring. You’ll want to make sure daytime temperatures consistently exceed 55 degrees F before setting out your transplants. In warmer weather climates, grow celeriac in the late summer so it’s ready to harvest in cool weather. Celeriac takes about 90 to 120 days to reach maturity.
How to Plant
Your celeriac seed will benefit from a 24 hour overnight soak in water to speed germination. Seed 1 1/2 inch pots filled with potting mix. The seeds tend to germinate best in about 70 degree temperatures.
However, because celeriac is a biennial, it must be tricked into thinking it has gone through a summer of growth. They must experience 10 consecutive days of 45 degree or below temperatures. The plants assume that winter is here, and once the temperatures begin to heat up, they think they’re in their second year of growth. They will put more energy into the foliage instead of the root. Harden off your celeriac when the days and nights are above 45 degrees F.
When transplanting seedlings, set them 8 to 10 inches apart in rows 24 inches apart. Gardeners oftentimes plant celeriac in a similar fashion to celery, in 3 to 4 inch deep trenches. As the plant grows, soil is mounded around the exposed root. Do not plant celeriac with pumpkins, cucumbers, or squashes.
When the plants are about 3 to 4 inches tall, mulch with straw to conserve as much moisture in the soil as possible.
Because celeriac is a shallow-rooted plant, it requires consistent, even watering. If the soil dries out, the celeriac will quit growing.
You can harvest celeriac when the roots are 3 to 5 inches across. Some feel that the flavor of celeriac is improved with a fall frost, and wait until after one to begin harvesting. The leaves and stalks can be added to dishes in place of celery.
The ideal temperature for storing celeriac is between 35 and 40 degrees F. In mild winter regions, you can overwinter celeriac right in the garden. In cold areas, a root cellar or cool basement can be used to store the roots. Avoid storing your celeriac with strong-flavored vegetables such as onions, however. The celeriac may pick up them up.
About the only pest known to cause trouble with celeriac are celery leafminers. Snip off affected leaves and destroy them.