Celery

Sow celery under cover in early spring, following the variety's recommended dates. Use small pots or modules filled with moist seed compost. Sow thinly on the surface: the seeds need light to germinate. Keep them warm, at least 15 °C, and moist without waterlogging them.

Germination can take up to three weeks. Once seedlings appear, give them plenty of light and keep them above 10 °C, as cold can encourage premature flowering later. Move them into individual pots when they are large enough to handle. Distinguish this pricking out from planting in the garden after acclimatisation and the last frost.

Use clean containers and lightly firm the compost before scattering the very fine seeds. Moisten with a fine watering rose or from below, without leaving the pots permanently standing in water. Label the sowing so you can follow its progress rather than relying on memory. Slow germination is not a reason to add water every day when the compost is still moist. When separating seedlings, hold them by a leaf and retain as many tiny roots as possible. Return them promptly to a bright position after handling, protected from cold draughts.

In a cool climate, starting celery under cover is usually more reliable because it needs warmth and a long growing season. If you sow outdoors, choose a suitable variety and wait for consistently warm conditions, following the dates on the seed packet.

Prepare a fine seedbed in fertile soil that retains moisture. Sow thinly on the surface rather than burying the seeds 0.5 cm deep, and water gently. Keep the surface moist. Thin or transplant the seedlings later to the spacing recommended for the variety; 10 cm is not the final spacing for mature celery.

Before choosing this method, compare the growing time given for the variety with the warm season actually available in your garden. A late sowing will not automatically produce well-developed stalks before cold weather returns. Mark the row and watch for the surface drying out, especially after a windy day. Use a fine spray so you do not wash the seeds away. Remove small weeds by hand without disturbing the celery seedlings. If the remaining season is too short, plan to use more advanced young plants for a suitably timed planting instead.

Plant celery in fertile soil that retains moisture, in a sunny or lightly shaded spot. Gradually harden off well-rooted young plants and wait until the last frost has passed and conditions are warm enough. Judge readiness by plant development rather than a fixed four to six weeks after sowing.

Keep the root ball intact and follow the variety's spacing instructions, often around 23 cm for green or self-blanching types. Water thoroughly after planting and maintain steady moisture. Apply mulch to limit drying and weeds, keeping it clear of the growing centre. Avoid pulling up plants when you only want to harvest a few outer stalks.

Water the modules before moving the plants and prepare holes that will take each root ball without crushing it. Keep the growing point visible at soil level: do not bury the heart. If possible, choose a mild day with little wind to reduce drying during establishment. Check particularly closely during the first few days, as the small root ball can dry out before the surrounding soil does. Distinguish green or self-blanching varieties from trench celery that needs blanching; do not automatically earth up every variety in the same way.

Harvest your celery when the stalks are large enough, according to the variety and planting date. Take a few outer stalks as needed, leaving the growing centre intact, or lift the whole plant for a complete harvest. Check the variety's frost tolerance before leaving it outdoors late in the season.

Handle the stalks gently and refrigerate them after harvest, using them soon for the best freshness. A cellar does not automatically keep cut celery longer than a fridge. For longer storage, you can freeze celery after suitable preparation for later use in cooked dishes.

To take just a few stalks, use a clean knife near their base and avoid tearing the tissues around the heart. Inspect the stalks before storing them and remove any that are damaged or rotting. Do not leave your harvest in the sun while finishing other garden jobs. Treat the calendar as a guide: do not strip a weak plant simply to reach a planned quantity. If a hard frost is forecast and your variety is tender, arrange to harvest before it is damaged rather than relying on a fixed date.