Celery is a crop of supreme excellence, for eating raw or cooked, and when well grown nothing equals it in crispness and flavour.
It requires rich soil, and moist – which does not mean waterlogged. Light soil has to be adapted by generous treatment with manure or rotted leaves and similar material.
Excellent varieties include Solid White, Giant White, Major Clarke’s Red, Standard Bearer (red).
At least 1,000 plants can be raised from an ounce of seed; germination takes about three weeks, more or less, according to temperature.
Ready for Use. Earliest in October; later sowings and plantings may not be ready until late November or December. Season continues to February.
Rich living and continual thirst quenchings are first considerations. The most satisfactory plan is to dig out a long trench, running north and south, about 10 in. deep, 18 in. wide at the bottom, the sides sloping slightly outwards. The soil taken out is placed on both sides of the trench, an equal quantity on each side, and patted down with the back of the spade to give it a firm slope and prevent any soil falling back into the trench.
The bottom of the trench is then broken up deeply with fork or spade and packed with rotted vegetable matter, or manure, or a manure substitute (such as hop manure). To make up for lack of these, bonemeal may be forked into the top 2 in. of the trench bottom after this has been broken up. Or a mixture of superphosphate of lime two parts, sulphate of ammonia one part, may be forked in similarly, but not until a week or so before planting. The bonemeal should be used as far as possible in advance of planting. The quantity to use, in both cases, is about 3 ounces to every 6 ft. of trench.
If the trench is prepared a couple of months in advance of planting, the soil banked up at the sides should be planted with lettuce, or sown with radish or spinach, so that no space is wasted. These crops will be used up before the celery plants are due for blanching – as explained later. If more than one trench is required they should be 4 ft. apart.
The Shallow-soil Trench.
Should chalk, stubborn clay, or similar hard subsoil lie within a few inches of the surface it would be useless making a 10-in. trench. Celery planted at that depth and in such circumstances would find neither the food nor the moisture which it demands. In this case the trench should be not more than about 4 in. deep, but the ground below should be broken up 1 ft. deep and, as far as is possible, enriched as though it were a really deep trench.
Plants accommodated in this manner cannot be earthed up so thoroughly as is desirable; and lacking the protection against frost given by the more ample soil covering which a deep trench makes possible they are less safe in winter. But the best must be made of circumstances.
Obtaining the Plants.
Celery for an early crop needs to be raised in a temperature of about 60 degrees, in March, for planting out in May. The maincrop is sown in April in a hotbed frame, or in an ordinary frame fully exposed to the sun, or in a sheltered but sunny spot outdoors.
Or young plants may be purchased for planting in the trench during the last two weeks of June – the usual time for the main crop, which is the most generally useful. For a late crop planting is done towards the end of July.
Sowing in a Box.
The seed box is filled fairly firmly with good sifted soil and sifted leaf-mould (or material from a worn-out hotbed or mushroom bed) in equal parts, mixed, plus silver sand or grit to ensure that it is porous. The seed is sprinkled very thinly on the smoothed surface, then only just covered with sifted soil. Glass is placed over the box top, then a sheet of paper to shade it; these are removed when the first seedling is visible.
Any old patch of soil will not suffice for open-air sowing in April. A small bed needs to be made for it – a 3-in. depth of mixture as advised for filling the seed box. Sow as directed in the preceding paragraph, and if a shallow, bottomless wooden box can be placed over the seed patch and the top covered with glass, germination will be speeded up.
The very small, indoor-raised plants require to be shifted when 2 in. high to other boxes, filled as before; in these they should stand 3 in. apart. They will remain in these boxes until planted out in the trench. The soil must never be allowed to dry out, and if there is any sign of yellowing of the foliage the plants will have to be fed with weak doses of one of the artificial fertilizer mixtures to keep them growing.
A temporary hold-up in growth may lead to the plants running up to flower later on.
Outdoor raised seedlings may remain in the seed bed if thinned out to about 3 in. apart, or be transplanted to another bed of rich and moist soil, until large enough for planting out.
The plants are put out – with a trowel – in the trench when they are 6 in. high, lifted from the outdoor bed or removed from the boxes with all the soil that will cling to the roots. An overnight soaking with water makes this final removal easier. Indoor or hotbed raised plants must be hardened off first, spending about a fortnight in the cold frame with plenty of ventilation, the boxes then being stood outdoors for a few days without any protection at all.
Removing Side Growths.
Side or sucker growths will arise from the roots. These must be watched for and broken away, or much of the strength of the plant will be wasted.
When the plants are about 9 in. high, soil from the trench-side mounds should be hoed or spaded into the trench so that about 4 in. of stem is covered, the soil to be worked close up to and completely around each plant, with the hands, the new surface being left level. As the plants increase
The sturdy young plants are set out 8 in. apart down the centre of the trench in a single line ; or if space is precious they may form two lines down the trench, separated by the width of the latter, the plants in one row alternating with those in the other. Leave them very firm in the soil and give a good soaking with clear water.
The soil of the trench needs to be kept moist, not with surface dribblings but with buckets of water so that this gets down below the roots. Feed occasionally with an artificial fertilizer, or with weak manure water if available, or with soot water (a heaped trowelful stirred up in each bucket of water used). Keep the water out of the plant centres or it may cause decay. in height, more soil will be mounded up around them until only the tops of leaves of the full-grown plants are visible.
When dealing with shallow trenches, soil will need to be scraped up to the plants with the draw hoe.
Earthing up should be done only when the soil from the sides is dry enough to handle, the trench soil first being watered.
It is necessary to prevent soil entering to the heart; this is arranged by tying the stems of each plant loosely together at die top before earthing up starts.
In dealing with heavy, wet soil it is advisable also to wrap brown or other fairly stout paper around each plant so that soil shall not actually touch the stems.
To complete the final cardiing up (after which, it should be borne in mind, plants will make no more growth) pat the sloping sides of the continuous ridge with the back of the spade to consolidate them so that rain runs easily down instead of soaking in.
The object of earthing up is to cause the stems to become white, by excluding light; in the natural green state they are bitter and uneatable.
Slugs and other Enemies.
It is the ambition of every slug anywhere near a row of celery to get into one of the hearts and play havoc there. They can be cheated of their prey by occasionally dusting the soil thickly with soot.
Bolting and Rotting.
Drought or starvation (or both) during early stages of growth will induce bolting – that is, running up to flower and seed; hence the need for constant attention to watering and sufficient food right from the sowing stage.
Celery will decay at the centre if water is allowed to penetrate there; hence the need for care with watering can or bucket.
Digging the Sticks.
The spade must be handled cautiously or stems may be severed during the lifdng of plants. The soil should be scraped down and away from one side of one plant at a time; when it is fully exposed, drive the spade blade slantwise beneath the root and lever the whole plant up and out.
Celery is ready for use about six weeks after the final earthing up.
Only in circumstances of extreme wet or cold need all die plants be lifted at once (that is when sufficiently blanched); they may then be dug up with all the soil possible clinging to the roots and packed in a sheltered spot against a fence or wall or in a shed, with plenty of soil mounded up against their exposed sides as protection.
Otherwise the plants are best left in the ground for lifting as wanted. In the event of hard weather they should be safeguarded by dry bracken or straw placed over the tops as a temporary covering. When hard frost threatens, a few plants should be lifted and taken indoors; it is not easy digging celery from frozen mounds.
Preparing for Table.
Wash the stems thoroughly; cut back green tips as far as the white; cut off roots, and trim the hard base neatly. Food value is not great. Raw or cooked, celery is popular, and holds a high place in invalid diets.