How to Grow Celeriac
Celeriac At a Glance
Difficulty
Moderate
Category
Vegetable
Sun Exposure
Full Sun
Frost Tolerance
Frost Hardy
Cold Hardiness
Survives to -7°C
Plant Family
Apiaceae
Growing Season
Cool Season
Plant Lifecycle
Biennial
How to Start It
★ Recommended for beginners
Celeriac is slow to sprout and needs a long season, so start it inside about 10 weeks before your last frost. Press the tiny seeds onto damp potting mix and barely cover them, about 0.3 cm, since they need light to sprout, then keep them warm and moist for the 14 to 21 days they take to come up. Plant them out about 2 weeks after your last frost, 25 cm apart, with the top of the root at soil level, not buried. Before planting out, set the pots outside in a sheltered spot for a few hours a day, a little longer each day for about a week, so they toughen up (this is called hardening off).
Celeriac is a cousin of celery grown for its round, knobbly root, which tastes like a mild, nutty celery. It needs about 110 days in the ground and never wants to dry out, which is why it is a little harder than most root crops. Young plants left out in cold weather for too long can flower instead of making a root, so wait for mild nights before planting out.
When To Start
Celeriac likes cool weather. Sow it in early spring, as soon as the ground can be worked.
We do not have exact sowing dates for this one yet.
When should you plant Celeriac?
Your planting dates depend on your local climate. Sign up and add your location to unlock personalized dates.
Your Celeriac Planting Window
Start planting
May 15, 2026
Last chance
Sep 10, 2026
Your Celeriac Calendar
Set your location to turn these into exact dates and reminders.
Start celeriac seeds indoors, barely covered, in a warm spot
10 weeks before your last frost
Plant celeriac out once nights are mild, root at soil level
2 weeks after your last frost
Dig celeriac roots before the ground freezes hard
Around your first frost
Start hardening off your celeriac seedlings: an hour outside today, a little longer each day.
4 days after your last frost
Water your new celeriac plants well while they settle in. Deep and slow is best.
About 1 days after you plant it
Your celeriac is growing! Keep it well watered, since it likes soil that never dries out.
About 58 days after you plant it
Your celeriac is swelling. Pull off low side leaves to show the bulb and help it grow round.
About 94 days after you plant it
Picking time may be here: check your celeriac.
About 110 days after you plant it
The Journey Ahead
Celeriac's Lifecycle
Seedling
Mature Plant
Seed Production
Step 2
Planting & Sprouting
Expect sprouts in 14–21 days
Growing Tips
- 1Grow celeriac in full sun, or light shade in the hottest part of the day.
- 2Mix plenty of compost into the soil, since it is a hungry plant that likes rich, moist ground.
- 3Water often enough that the soil never dries out, and spread mulch to hold the moisture in.
- 4Feed with compost tea or worm castings every 3 to 4 weeks through summer.
- 5In late summer, pull off a few of the lowest leaves and any side roots near the top so the root swells round and smooth.
- 6Pick slugs off young plants in the evening, and use row cover to keep off carrot rust fly, a small fly whose grubs tunnel into roots.
Seedling Phase
Step 3
Growth & Maturity
~110
Days to Maturity
40 cm
Mature Height
30 cm
Mature Width
Pests to Watch For
Diseases to Watch For
Mature Plant
Step 4
Harvesting
Harvest Window
30 days
When to Pick
Lift in autumn once the bulbs are tennis-ball-sized or larger
How to Harvest
- 1Start digging in fall once the roots are 8 to 12 cm across, about the size of a large orange.
- 2Light frost does no harm, but dig them all before the ground freezes hard.
- 3Loosen the soil with a fork and lift the root, then cut off the leaves and trim the small roots.
- 4Use the leaves like celery to flavour soups and stocks.
- 5Store the roots in a bag in the fridge for a few weeks, or in damp sand in a cold cellar for several months.
- 6Peel off the thick, knobbly skin before you cook or grate it.
Step 5
Saving Seeds
How to Save Seeds
Celeriac only flowers in its second year, after a winter. Store a few of your best roots in damp sand somewhere cold that does not freeze, and replant them in spring. They send up stalks with flat, umbrella-shaped flower heads, and insects carry their pollen to celery too, so let only celeriac or celery flower within about 800 m. Hybrid F1 seeds will not grow true. Cut the heads when the seeds turn brown, dry them in a paper bag, rub out the tiny seeds, and store them labelled in a cool, dark, dry place for 3 to 5 years.
Seed Production
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