How to Grow Celery

Celery is an important vegetable for the kitchen as it is used, at least in part, in many dishes, including basic recipes such as stocks. Its culinary importance is not reflected in the garden, however. At one time no vegetable garden was complete without celery, but it is seen less often today, which may be partly because it is slightly difficult to grow and partly because it needs a constantly moist soil to do well. Whatever the reason, it is a shame it is not more widely grown, because if you do grow it you will find that you are constantly using it and, as always, will find the flavour so much better than shop-bought stalks.

Celery grows wild throughout Europe and Asia, and it is rather surprising to learn that it has entered cultivation only in relatively recent times. Celery was first cultivated in Italy as recently as the 16th century but it did not arrive in Britain until the end of the 17th century.

It is the blanched leaf stalks of celery that are eaten. These can be eaten green but taste sweeter if the light has been excluded, causing the stalks to turn white. This always used to be done by heaping earth up round them, but more often these days the stems are wrapped in cardboard or felt. This type of celery is often referred to as trench celery. Breeding has produced celery with self-blanching stems, although not everybody feels that these are wholly successful and that the old-style blanched stalks taste better. There are also forms with green, pink or red stems. There is a form of celery, known as green or American celery, which does not require blanching.

As well as the stems, some people like to eat the heart, the solid part of the plant, where the stems join the root. Some recipes also call for the leaves to be included, particularly when the celery is a flavouring agent rather than a vegetable in its own right. It can be cooked or eaten raw.

Cultivation

There are two ways of growing celery, depending on what type is being grown. To grow traditional trench celery, in the preceding autumn or winter dig out a trench 45cm/l8in wide and 30cm/l2in deep and put in an 8cm/3in layer of rotted manure. Backfill the trench, leaving it about 10cm/4in deep. Sow the seeds under glass in modules in early spring and place them in moderate heat of 10-16°C/50-61 °F. Do not check the plants by subjecting them to a sudden change of temperature or by allowing them to dry out. Once the frosts are over, harden off the plants and plant them out in the trench at 30cm/12in intervals. When the plants reach about 30cm/12in, tie the stems loosely together just below the leaves and draw up earth over part of the stems. Repeat the process three weeks later, pulling up more soil, and again three weeks after this, until the soil is up to the lower leaves. Alternatively, plant on flat ground and wrap cardboard or waterproof paper round the stems when they are 30cm/12in long. When the stems grow taller, wrap a second collar round them. Keep the celery well watered and do not allow the soil to dry out.

Sell-blanching celery is started in the same way from seed and then planted out in blocks rather than rows, setting the plants at intervals of 23cm/9in in all directions. The dense foliage helps to blanch the stems. Place straw around the outside of the block to help keep out the light. Green celery can be grown in the same way, although there is no need for the straw.

Harvesting

Trench celery can be lifted in autumn by digging it up with a fork. Replace soil around the next plant if it falls away. Continue to dig as required. The flavour is improved by the first frosts, but cover the plants with straw in severe weather so that penetrating frosts do not reach the stems. Self-blanching celery can also be harvested as required from the autumn onwards, but it should be lifted by the time of the first w inter frosts.

Storage

Leave trench varieties where they are growing until required. In colder areas, before the weather becomes severe, lift and store in a frost-free place, where they should stay fresh for several weeks. Celery can be frozen, but it becomes mushy when it is defrosted, so it can only be used as flavouring or in cooked dishes.

Pests and diseases

Slugs are one of the worst enemies of celery, and it is important to cull them regularly by your preferred method. Other problems can include celery fly and carrot fly.

Diseases include celery heart rot and cel­ery leaf spot. Boron deficiency, which causes the stems to crack, may also be a problem.

Further Readings: