Stem
How to grow celery
Apium graveolens var. dulce
Celery is a bog plant by origin, and growing it well means recreating those conditions: soil full of organic matter that stays moist from planting to cutting. Sow on the surface of the compost with warmth in March or April, keep seedlings above 10 °C, and plant out in late May or June, once frosts are over. Self-blanching varieties planted in a block are the simplest and are cut from August until the first hard frost.
- Hardiness
- Half-hardy; trench types stand into winter
- Position
- Sun, tolerates light shade
- Soil
- Very rich, moisture-retentive (bog-like)
- Ideal pH
- 6.5 to 7.0
- Water
- Very high, never let it dry
- Feeding
- Heavy feeder
Sowing and planting celery
WhenSow Mar to Apr with heat; plant out late May to Jun; harvest Aug to Dec
Starting off
Sow March to April on the surface of a seed tray, uncovered or lightly dusted with vermiculite, at 15 to 18 °C under light, germinating slowly in 14 to 21 days; temperatures below 10 °C for the first weeks cause bolting. Prick out into modules, harden off gradually and plant out late May to June at 8 to 10 cm tall, watering the hole first.
Spacing and planting
Self-blanching types 23 to 25 cm apart each way in a block, so the plants shade and blanch each other; trench types 30 cm apart in a 40 cm wide, 30 cm deep trench, earthed up in stages from August. Plant at module depth, never burying the crown. Not a container plant.
Varieties worth growing
- Victoria F1
- Green self-blanching type that is slow to bolt and stays crisp; the most reliable for a first attempt.
- Loretta F1
- Self-blanching, with pale, smooth, stringless stems and good vigour. Ready from late August.
- Golden Self Blanching
- The traditional open-pollinated self-blanching celery: compact, early and cream-yellow, but it must be cut before frost.
- Giant Red
- Hardy trench celery with red-flushed stems that stands under straw into December. More work, more flavour.
- Par-Cel
- A leaf celery grown like parsley and cut for soups and stock. It gives the flavour without the blanching, and tolerates drier soil than stem celery.
Celery month by month
Timings are for central England. Allow two weeks later in the north and on cold, heavy soil.
- January
Nothing to do. Order seed.
- February
Dig a bucket of compost per square metre into the bed, or dig the trench for trench types.
- March
Sow on the surface of the compost at 15 to 18 °C from mid month. Do not cover the seed.
- April
Last sowing early in the month. Prick out into modules. Keep seedlings above 10 °C.
- May
Harden off slowly over two weeks. Plant out at the end of the month, once nights stay mild.
- June
Plant out in blocks. Water every plant in. Top-dress three weeks after planting. Mesh against leaf miner and carrot fly.
- July
Water heavily twice a week in dry weather. Nitrogen top-dress.
- August
Cut the first self-blanching heads. Start earthing up trench types, 8 cm at a time.
- September
Cut self-blanching celery as needed. Continue earthing up. Keep watering if it is dry.
- October
Finish the self-blanching crop before the first hard frost. Dig the first trench celery.
- November
Dig trench celery as needed. Cover the tops with straw in frosty weather.
- December
Dig the last trench celery.
Feeding celery
A hungry, shallow-rooted crop that can only feed from moist soil. Organic matter and water come first; fertiliser on dry ground does nothing for celery.
Hungry and very thirsty, masses of organic matter and steady feeding. Never let it dry.
Feeding plan
February or March, before planting
Garden compost
One 10 litre bucket per square metre dug into the top 20 cm, or a 10 cm layer in the bottom of a trench. This is what holds the water.
A week before planting out
Fruit & Vegetable Fertiliser 4-5-6
100 g/m² raked in. A block at 25 cm each way holds 16 plants per square metre, so that is about 6 g per plant.
Mid to late June, about three weeks after planting, once
Fruit & Vegetable Fertiliser 4-5-6
50 g/m², about 3 g per plant in a block (50 divided by 16), scattered between the plants, kept off the leaves and watered in. That brings the season to the label limit of 150 g/m², so no more of this fertiliser afterwards.
Early July, once
Organic Nitrogen Fertiliser 13% N
25 to 40 g/m², roughly one rounded handful per square metre of block, scattered between the plants, kept off the leaves and watered in.
Before planting, only where earlier celery had cracked, brown-striped stems
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
Blackened, dead central leaves (blackheart)
Calcium not reaching the heart in a dry spell, not a soil shortage
Water copiously and steadily
Cracked stems with brown stripes
Boron short, worst after liming
Seaweed feed or a light borax dressing
Stringy, bitter stems and a flower spike
A check from cold or drought
Sow later and never let it dry
Pests, diseases and problems
Brown, dry, papery blotches on the leaves, with a small white maggot inside when held to the light
Celery leaf miner, the larva of the celery fly; attacks from May, with a second generation in late summer
Pinch off and bin affected leaflets as soon as you see them, and cover young plants with fine insect mesh. Do not plant seedlings that already have blistered leaves.
Stems rasped and scarred, with slime trails in the heart; damage worst inside earthed-up trench celery
Slugs, which thrive in the constant damp this crop needs
Apply slug nematodes to the moist soil in June and again six weeks later, clear debris from around the block, and search with a torch before earthing up.
Small brown spots on leaves and stalks, each with pinprick black dots, spreading fast in wet weather
Celery leaf spot (Septoria), carried on the seed and spread by rain splash
Buy seed from a reputable supplier, as good seed is treated or tested. Remove spotted leaves at once, water at the base and not over the top, and keep to a three-year rotation.
Plants stunted with yellowing outer leaves; rusty tunnels in the root and stem base
Carrot fly, which attacks celery and celeriac as well as carrots
Fine insect mesh over the block from planting, with the edges buried.
The heart turns brown and slimy and the plant collapses at ground level
Bacterial soft rot entering through slug wounds or frost damage
Control slugs, do not let soil fall into the heart when earthing up, and cut self-blanching types before the first hard frost.
Harvest and rotation
Harvest and storage
Cut self-blanching types from August when stems are 30 cm and the plant 20 to 25 cm across, 25 to 30 weeks from sowing, lifting whole with a fork; trench types are dug October to December after 6 to 8 weeks of earthing up, sweeter after frost. A plant gives one 500 g to 1 kg head. Keep 2 weeks in the fridge; trench types stand under straw until Christmas.
Rotation and companions
Rotation: umbellifer (carrot) family with carrots, parsnips and celeriac, 3-year gap, usually sited with the hungry brassicas on manured ground. Leeks and brassicas alongside share the rich, wet regime.
Good to knowSelf-blanching types grow in blocks; trench types are earthed up. Any check causes stringiness or bolting.
Growing celery in pots
Stem celery is not suited to pots. It needs more water than any container can hold between waterings, and a single dry day gives stringy, bitter stems or sends the plant to seed. Self-blanching types also rely on being packed in a block to shade one another. The exception is leaf celery such as Par-Cel: three plants in a 30 cm pot (about 15 litres) of peat-free compost, with 5 g per litre of the 4-5-6 mixed in, which is 75 g, will give cut-and-come-again leaves from June to November. Keep the pot in light shade and stand it in a saucer of water in hot weather.
Celery: common questions
Why is my celery stringy and bitter?
It ran short of water at some point. Celery that dries out, even briefly, lays down tough fibres and turns bitter, and no later watering reverses it. Dig in plenty of compost before planting, water heavily twice a week in dry weather, and cut self-blanching types as soon as they are ready, not weeks later.
Do you have to blanch celery?
Not with self-blanching varieties, which is why most gardeners now grow them. Planted 25 cm apart in a block, the plants shade each other and the stems stay pale and mild. Trench varieties do need earthing up in stages from August to keep light off the stems.
Why has my celery bolted?
A cold spell in the seedling stage is the usual cause. Young celery held below 10 °C for more than a few days is triggered to flower later in summer. Sow in March or April, not earlier, keep seedlings warm, harden them off gradually and do not plant out before late May.
Sources
Growing information on this page was checked against these references in November 2026. Feeding rates are Dr Forest label rates.