Tips on how to grow celery

Celery is a wonderful flavourenhancer in soups and stews. A great cut-and-come-again crop, you can harvest a few stalks at a time as needed. Homegrown celery often has slimmer stems than a commercially grown crop but don’t worry, just add more skinny stems than the recipe calls for and throw in some leaves, too.

SOW AND GROW

Sow seeds: January to May in warm areas; October to January in cooler areas. Transplant seedlings: March to July in warm areas; January to April in cooler areas.

Position: Full sun, six or more hours a day.

Harvest: 14-20 weeks from seed.

START CELERY IN COOLER WEATHER

Celery can be grown all year round but does best during the cooler months of spring and autumn. Seed should be sown from mid-spring until mid-summer in cool parts of the country and midsummer until early autumn in warm areas.

It can take up to a month to germinate, plus an average-sized family only needs three or four plants, so it may be easier to plant a punnet of seedlings. Celery can be frost-tender, so seedlings should be planted out by mid-autumn in cooler parts of the country, but you can get away with planting until midwinter in frost-free areas.

STEP-BY-STEP

Celery seed is tiny so is best sown in trays, then transplanted out later. It needs light to germinate so just lightly press the seed into moist seed-raising mix. Seedlings are slow to emerge but should appear in two or three weeks. Space 30cm apart, allowing 60cm between rows.

GROWING TIPS

Celery is a hungry plant. Prepare soil well by digging in compost, sheep pellets and blood and bone. It grows best in a mild or cool climate and can become stringy and bolt to seed in hot weather if it’s not watered every couple of days. Adding a layer of mulch around plants will help conserve moisture.

Because it’s notoriously slow growing, celery needs far more fertiliser than green crops such as lettuce. If you want thick stalks, side dress with blood and bone twice during its growing season. To harvest, slide your thumb down the inside of the fattest outer stalks and gently twist to pull them off the plant. Don’t cut the stalks off

as the cut stumps left behind will rot.

STANDOUT VARIETIES

For warmer areas, boltresistant varieties include ‘‘Slowbolt Polo’’ or ‘‘Tall Utah’’, which grows to 60 centimetres tall. Speedier French variety ‘‘Elne’’ matures 13 weeks after transplanting, or go for dwarf variety

(up to 45cm) ‘‘Celery for Cutting’’, which matures 11 weeks after transplanting and is ideal for containers – but should be watered daily when grown in a pot.

‘‘Golden Self-Blanching’’ has creamcoloured stalks and a milder flavour than other varieties, which may be more palatable to people who find celery bitter.

TROUBLESHOOTING

Celery is beloved by slugs and snails, so go out at night to pick off and squash any slimy garden invaders. Aphids can be a problem too, so squirt off the stalks with the hose or use a garlic and soapy water spray.

Black or brown spots on the leaves are a type of rust called septoria leaf spot. This fungal disease affects the oldest leaves and stems first, and if you pick the outer stems often (before they show spots) you can stay ahead of it. Sudden changes in temperature and lack of moisture can cause plants to bolt to seed without forming stalks, so water well, especially during dry weather.