Given a warm summer, an outdoor crop of cucumbers is not difficult to procure. The requirements, in addition to sun heat, are rich soil and a warm root run (which means fresh manure down below), moist conditions above and below, and a suitable variety of cucumber for cultivation in the open.
These items cannot be called exacting; and when the prize is freely produced fruit (for fruit it is, though accepted as a vegetable) only a trifle short of hot-house standard, every exertion on the grower’s part is most adequately rewarded.
Varieties for outdoor growing include King of the Ridge (a beautifully straight cucumber, sometimes reaching 16 in. in length). Long Green, Prolific, Stockwood, Bedfordshire Prize, Long Prickly and Short Prickly or Gherkin, which is just right for pickling. These are true ridge cucumbers and should not be confounded with varieties for greenhouse and hotbed frame cultivation. They are called ridge because it is customary to grow these outdoor varieties on ridges or mounds of soil above a few inches of manure.
There are approximately 500 plants in an ounce of cucumber seed. Germination takes about ten days – more or less, in accordance with temperature.
Ready for Use. Early August and September, outdoors. Earlier crops are available from a hotbed frame, still earlier from a heated greenhouse, as explained later.
The ideal procedure is as follows: a bucketful of fresh manure is dumped in a heap where each plant is to be grown (in full sun) and on top of that two buckets of good soil are placed. Light, sandy soil is unsuitable; it should be of heavy and moisture-holding nature. The soil is firmed down, and is then ready – in late May or June – to receive indoor-raised plants; or two seeds may be sown on each heap in late May.
Alternatively, dig a hole for each plant 2 ft. in diameter and 1 ft. deep, placing the excavated soil on the north side (to break the wind) and emptying a bucket of manure into the hole. Tread the manure down and cover with about 4 in. of soil, in readiness for planting or sowing. This is the better plan when the ground is light and parts easily with its moisture.
It is desirable that the manure shall be fresh, to supply the necessary bottom heat. Enough can sometimes be secured from road scrapings, and the manure can be made to go farther by mixing widi it an equal bulk of tree leaves – last year’s, collected from below woodland trees.
When and How to Sow.
Naturally, plants for setting out are obtained earlier from an indoor than an outdoor sowing. If a temperature of about 55 degrees is available, as in a heated greenhouse or hotbed frame, ridge cucumbers can be raised from seed sown in late April or early May, for planting out in late May or June. Three-inch pots are filled with good, sifted soil, and in the centre of each a single seed is sown, on edge and about 1 in. deep. Cover the sown pots with paper and glass, remove this covering when the seedlings are breaking through the soil and stand them in full light close to the glass.
Seed raised in a hotbed frame will germinate more quickly if the pots are sunk to their rims in the hotbed material or in the soil covering it.
Seed may rot before it can germinate if the soil is kept too wet, and young plants may rot at the collar (surface level) unless watering is deferred until need for it is apparent.
Planting Out Ridge Cucumbers.
By the time weather is safe for planting out (late May or early June) the plants will be about 6 in. high and the pots filled with roots. Plants that have made rather more progress should not be left to starve in the 3-in. pots until planted out; they should be moved into 5-in. pots filled with really rich soil (old, rotted manure, or sifted leaf-mould, mixed with good garden soil).
A few days spent in a cold frame, with plenty of air whenever possible, will accustom them to hardier conditions. They can then be turned out of the pots, the crocks removed from the unbroken soil-and-roots mass, and planted singly on the prepared heaps or ridges, or in the manured holes, as deep as the lowest leaf.
After Planting Out.
Until late June the planted out ridge cucumber plants run some risk from the weather. To lessen this risk they should be covered each night with large inverted flower pots, or with boxes. Progress will be brisker if, for the pots or boxes, sheets of glass can be substituted, these remaining in position (with a crack of air) during chilly day periods.
For a week or so after planting out not much water will be required (after the initial watering-in), but once growth recommences the can will be in frequent demand.
The alternatives to raising ridge cucumbers under glass are to sow outdoors, in the prepared places (where the plants are to remain), in late May, or to purchase plants from a nurseryman. Bought plants should be deep green in colour and short jointed; if light in colour and lanky, refuse them.
The attempt is often made to raise cucumber (and other) plants in a warm airing cupboard or similar heated place indoors. The seed germinates quite satisfactorily, but the snag lies in what to do with the seedlings when they come out into full light, the move being accompanied by a noticeable drop in the temperature of their surroundings. The consequent check to growth sets them back to a marked extent. Nothing is gained by attempting this; outdoor sowing is better in every way.
Set two seeds in each heap or ridge or prepared hole, 1 in. deep, on edge and 3 in. apart. Cover at once with a glass jam-jar or sheets of glass, or a glass-topped box, shaded with paper until the seedlings are visible. Then remove the shading and give air by degrees, until the protection can be removed altogether.
Only the stronger of each pair of plants is to remain. As soon as it can be seen which is the better, the weaker should be pulled out.
Training Outdoor Cucumber Plants.
When the plant is about 1 ft. long (the habit is trailing – stakes not required) the growing point should be nipped off. This operation is known as stopping, and the result is the production of side shoots (known as laterals) on which flowers and then the cucumbers will form.
The tips of the side shoots should be nipped off a little way beyond the joint that comes next after the tiny fruit. These side shoots are produced in quantity, and the weakest of them should be removed completely.
The yellow flowers that come before the cucumbers are either male (pollen-bearing) or female. Only the latter bear fruit – the immature cucumber can be seen as a distinct bulge behind each female flower – and the fruit develops without fertilization. Only if seed is required should pollen be transferred to the central organs of the female flowers.
Watering and Feeding.
Drought is fatal to these plants. A bucket of water should be given to each plant as often as watering is necessary, and they should be syringed, or dewed overhead from a watering can fitted with a fine rose, every warm and dry morning and evening. Sun-warmed rainwater is best; cold water straight from a tap is apt to check growth.
If roots (like whitish cords or threads) appear at the surface, a top dressing of rich soil, put down about 2 in. thick and compressed with the fingers, will help fruiting tremendously.
When a heavy crop of fruit is formed, give a dose, once a week, of dried blood, a teaspoonful in each 2 gals, of water, or the same amount of superphosphate of lime.
Leaves showing signs of decay should be cut or nipped off and removed to the soft rubbish heap or the bonfire.
Protection for the Cucumbers.
The undersides of the fruits, where they lie fiat on the soil, may become discoloured unless a piece of board or slate is placed beneath.
Cucumbers in a Frame.
Ridge varieties can also be grown in a cold frame, where the plants are under better control (as regards sun heat, and moist atmosphere) than outdoors. Sowing and planting details are the same, but the plants are trained as explained here for hotbed crops.
A hotbed frame will give an earlier crop, from June onwards, if ventilation, conservation of heat and moisture, top dressing and other details as outlined for ridge cucumbers are carefully attended to.
Varieties for hotbed frame and warm greenhouse cultivation include Improved Telegraph (noted for prolific bearing and its small neck and excellent flavour), Every-day, Tender and True, Long White, Lockie’s Perfection and Rochford’s Market.
Sow seed in February, March or early April (as advised for ridge varieties); plants to be set out in the hotbed frame when about 6 in. high. A single-light frame will accommodate one plant, a two-light frame two plants. Dealing with a single-light frame, make up a mound of soil in the centre – about four pailfuls of loam and sifted leaf-mould and a good scattering of wood ash from the bonfire, and in the centre of it place one plant, the top of the ball of soil and roots being covered about in. deep.
This soil must not be too fine or it will remain sodden and the plant will suffer.
When the plant has increased to about 9 in. in length remove the growing point. Two of the strongest side shoots which result should have their ends nipped off when about 6 in. long. That will result in four strong shoots – one for training to each corner of the frame.
More side shoots will speedily develop and produce flowers and fruit, each fruiting shoot to have its tip removed at one joint beyond the fruit, as explained for ridge varieties.
The thinning out of weak shoots and crowded leaves is important, to ensure free circulation of air and plenty of light.
As roots show through the surface, cover with 2 in. of rich soil. Watering, syringing and feeding to be carried out as already explained.
Ventilation and Moisture.
A temperature of 80 degrees by day is to be aimed at, and 55 degrees by night. Give only a little air at any time (cold draughts must be guarded against), and as soon as the plants and the whole of the interior of the frame have been syringed (with lukewarm water) in the afternoon – about five o’clock – the frame should be shut right down and remain closed until air is given next morning.
Some form of thin shading should be provided during the brightest part of the day, or leaves may be scorched. Single sheets of newspaper placed over the glass (held down by pieces of board or brick) will serve, the shading to be removed as danger of scorching passes.
If a day temperature of 80 degrees and a night temperature of 55 degrees can be maintained in winter, it is possible to have cucumbers all the year round. For winter supplies, seed is sown in September or October; for an early-year start a January sowing is necessary; February or March for a summer crop.
Young plants are set out in mounds of soil about 18 in. apart on the greenhouse bench, each provided with a stake to carry it up to the wires running horizontally beneath the roof glass. If these training wires are not present, long canes may be substituted, fixed horizontally 9 in. from the glass.
Training Greenhouse Cucumbers.
Each plant is tied loosely, at intervals of a few inches, to its upright stake – loosely, to allow stems to expand. The growing point of the main stem is not nipped off until the top of the greenhouse is reached, but side shoots that appear before the first horizontal wires or canes are reached should be removed completely. Thereafter training consists in tying side shoots sideways to die supports and stopping them at the first joint beyond the fruit, removing weak shoots and overcrowding leaves.
Watering, syringing, top dressing, shading, ventilation should be carried out as explained for hotbed frame cucumbers.
Water of the same temperature as the house is to be used for watering and syringing. An effect of the latter may be to give an always-damp appearance to the soil; this must not be taken as evidence of the condition of the soil below. To determine whether roots are getting all the moisture they require, push a stick or piece of cane 6 in. or 8 in. into the soil, withdraw it and examine the soil which adheres to the end. If this is really moist, conditions are right; if it is not moist, give water at once.
Soil used for covering surface roots (top dressing) should be warmed to the temperature of the house before being put down.
If leaves are deep green in colour, all is well; a yellowish tint is a sign that too much water is being given, or the temperature is too low, or insufficient light is reaching them.
These conditions apply also to hotbed frame cucumbers.
Troubles and Remedies. Almost invisible mites known as red spider nourish on plants in a too dry atmosphere. The pests congregate on the underside of leaves and suck out the sap so that the foliage has a sickly appearance. Hence the necessity for repeated syringings, below the leaves and overhead and sideways, all the interior woodwork and brickwork of greenhouse or frame also being kept moist.
Green fly may put in an appearance. It should be checked by spraying with one of the proprietary insecticides; or greenhouse or frame may be fumigated.
Woodlice, if troublesome, can be trapped by placing pieces of decaying board here and there on the soil; the woodlice will seek these hiding places and can be collected and destroyed.
Eelworm is an underground worker, attacking the roots and forming knobs or swellings thereon. An affected cucumber plant, which ceases to grow, and wilts, should be uprooted and burnt, and the soil taken out and buried.
Mildew on the leaves is checked by dusting, after a light syringing, with flowers of sulphur; the treatment to be repeated on second and third days.
Leaf-spot disease is evident as yellow or brown spots spreading into extensive blotches; any cucum- ber plant so attacked should be removed and burnt.
Canker eats into the base of the main stem and the plant is destroyed unless the disease is dealt with promptly. The cankered part should be bared – by scraping away as much of the soil as necessary – then dressed with slaked lime or flowers of sulphur, the powder to be well rubbed in.
Gathering the Cucumbers. These should be cut whilst the withered flower is still attached to the far end and before there is any indication of the fruit yellowing at the stem end.
Preparing for Table.
Pare off the green skin, and if the cucumber is to be sliced start cutting from the lower end; the stalk end is always bitter. As a food, cucumbers are low down in the scale, and are not too digestible; but those facts are outweighed by their tastiness and their value in every salad bowl.