Stem and root
How to grow celeriac
Apium graveolens var. rapaceum
Celeriac gives the flavour of celery from a swollen stem base that keeps all winter, and it is the easier of the two to grow: no blanching, fewer problems and it stands frost. What it does need is time and water. Sow under cover in February or March, plant out in late May or early June with the crown level with the soil surface, and keep the ground moist all summer. The base does most of its swelling in September and October.
- Hardiness
- Hardy, lift before hard frost or mulch
- Position
- Sun to light shade
- Soil
- Very rich, moisture-retentive
- Ideal pH
- 6.5 to 7.0
- Water
- Very high, steady moisture all summer
- Feeding
- Heavy feeder
Sowing and planting celeriac
WhenSow Feb to Mar with heat; plant out May to Jun; harvest Oct to Mar
Starting off
Sow February to March on the surface of a seed tray at 15 to 18 °C under light, germinating in 14 to 21 days; prick out into modules and grow on at 10 to 15 °C, never below 10 °C for long, or it bolts. Harden off for 10 days and plant out late May to June at 8 to 10 cm tall, watering the hole first. 'Prinz' and 'Monarch' are reliable.
Spacing and planting
Plant 30 to 35 cm apart in rows 40 to 45 cm apart, with the crown sitting at soil level, never buried; firm gently. Not a container plant, since the swollen base needs a long season in deep, constantly moist soil.
Varieties worth growing
- Prinz
- Slow to bolt and resistant to leaf disease, with a round, medium-sized base. The dependable choice for a first crop.
- Monarch
- Smooth skinned, so less is lost in peeling, with firm white flesh that keeps well in store.
- Giant Prague
- The old heritage variety. Large and knobbly with a strong flavour, but it needs the full season to size up.
- Ibis
- Quick to bulk up, giving usable roots from September; worth growing where the season is short or planting is late.
- Brilliant
- Smooth, round roots with white flesh that is slow to discolour once cut; good for eating raw in remoulade.
Celeriac month by month
Timings are for central England. Allow two weeks later in the north and on cold, heavy soil.
- January
Lift from under straw as needed. Order seed.
- February
Sow on the surface of the compost at 15 to 18 °C. Lift the last roots on wet soil.
- March
Sow by mid month. Prick out into modules. Last roots from the ground before they regrow.
- April
Grow on in good light, never below 10 °C. Dig compost into the bed.
- May
Harden off for 10 days. Plant out at the end of the month, once frosts are over, with the crown at soil level.
- June
Finish planting. Water in. Top-dress three to four weeks after planting.
- July
Water weekly, twice in drought. Mulch with compost.
- August
Start pulling off the lowest leaves and any side shoots to expose the crown.
- September
Keep watering; the base is swelling fastest now.
- October
Lift the first roots at 10 to 12 cm across.
- November
Cover the row with straw, or lift and store in damp sand on heavy soil.
- December
Lift as needed.
Feeding celeriac
A long-season crop fed early: a base dressing, one top-dress in late June, and steady water after that. Too much nitrogen late on gives a fine top of leaves over a small base.
A long-season feeder, feed steadily and keep moist all summer.
Feeding plan
April, before planting
Garden compost
One 10 litre bucket per square metre dug into the top 20 cm.
A week before planting out
Fruit & Vegetable Fertiliser 4-5-6
100 g/m² raked in. At 30 by 40 cm each plant has 0.12 m², so that is 12 g per plant.
Late June, three to four weeks after planting
Fruit & Vegetable Fertiliser 4-5-6
50 g/m², 6 g per plant, scattered between the rows and watered in. That brings the season to the label limit of 150 g/m², so feeding stops here. From July the crop needs water and a mulch, not more fertiliser.
Before planting, only where earlier roots were hollow or brown at the centre
1 to 2 g/m², a quarter to half a level teaspoon per square metre, scattered evenly, once a season and never exceeded.
Signs to watch
Hollow, cracked or brown-centred crowns
Boron short, worst after liming, or erratic water
Seaweed feed, a light borax dressing and steady watering
Small crowns with lush leaf
Excess nitrogen or side shoots left on
Stop late feeding and strip lower leaves from August
Bolting
A cold check as a seedling
Keep seedlings above 10 °C
Pests, diseases and problems
Brown, papery blisters on the leaves with a maggot visible inside
Celery leaf miner. Celeriac tolerates it better than celery, but a bad attack on young plants reduces the size of the base
Pinch off blistered leaflets, and cover the bed with fine insect mesh from planting until July.
Holes rasped into the top of the swelling base, and young transplants eaten off
Slugs
Slug nematodes on moist soil after planting, repeated six weeks later; keep the stripped lower leaves off the bed.
Rusty brown tunnels in the base and roots, found at lifting
Carrot fly larvae
Fine mesh over the crop from planting, edges buried; keep celeriac in the same meshed bed as carrots and parsnips.
Small brown leaf spots with tiny black dots, spreading in a wet summer
Celery leaf spot (Septoria), which is seed-borne
Buy fresh seed from a reputable supplier, remove affected leaves, water at soil level and rotate on a three-year gap. Prinz has some resistance.
Roots left in the ground turn soft and brown inside after a hard spell
Frost penetrating the exposed top of the base
Cover the row with 15 cm of straw or bracken from November, or lift and store in damp sand before prolonged hard frost.
Harvest and rotation
Harvest and storage
Lift from October when the base is 10 to 12 cm across, 30 to 35 weeks from sowing, sweeter after frost; ease out with a fork and twist off the leaves, leaving a 2 cm tuft. A plant gives one 500 g to 1 kg root. Leave in the ground under straw until March on well-drained soil, or lift in November and store in damp sand.
Rotation and companions
Rotation: umbellifer (carrot) family with carrots, celery and parsnips, 3-year gap, grouped with the hungry crops on manured ground. Leeks and brassicas alongside like the same rich, moist soil.
Good to knowRemove lower leaves and any side roots from late summer to swell the crown; it needs a long, unchecked run.
Growing celeriac in pots
Celeriac is not worth growing in a pot. It occupies the container from May to at least October for a single root, and the base only swells properly where the soil is deep and constantly moist, which a pot in August is not. Plants that dry out stay the size of a tennis ball. If a raised bed is all you have it does well there, at 30 cm each way, provided the bed is at least 25 cm deep, has plenty of compost in it and is watered through dry weeks. A mulch after planting halves the watering.
Celeriac: common questions
Why is my celeriac so small?
Usually a late start or a dry summer. Celeriac needs about six months of unbroken growth, so sow by mid March and plant by early June. Water every week in dry weather, especially in September, and plant with the crown at the surface, as a buried crown does not swell properly.
Should I remove the leaves from celeriac?
Yes, the lowest ones, from August. Pull off the outer leaves that have flopped to the ground, along with any side shoots, so the top of the base is exposed and the plant's energy goes into swelling it. Leave the upright central leaves alone.
Can you leave celeriac in the ground over winter?
Yes on well-drained soil, under a 15 cm layer of straw, and it can be lifted as needed until March. On heavy, wet ground, or where slugs are bad, lift in November, twist off the leaves and store the roots in boxes of damp sand in a cool, frost-free shed.
Sources
Growing information on this page was checked against these references in November 2026. Feeding rates are Dr Forest label rates.