Part 2

A reference to the sketch, will at once shew the general nature of the internal arrangements. There should be a tank (_d_) supported by brick piers (_p_) in which a circulation of heated water would supply a genial warmth to the soil above, and to the roots of the plants growing in the soil; this tank should be heated by a small boiler, conveniently placed with reference to adjacent arrangements; a series of iron pipes (_e_) attached to the same boiler, would supply the requisite heat to the atmosphere. It may perhaps be thought that the application of the gutter system of heating would in this case be preferable; but as there would be a perfect command of moisture, as will be explained further on, it is desirable to have dry heat also, under controul, and this can be better effected by means of the pipes than by adopting the gutter plan of heating. I cannot in this place forbear protesting against the limited surface of piping generally employed in heating plant structures; what is thought to be just enough to maintain a given temperature, is usually after minute calculation, the quantity which is made use of, and the consequence is, that under adverse circumstances, the apparatus is necessarily worked at its highest pitch; and I believe that the application of heat in this form, whether it be by means of an hot water apparatus, or by a common flue, is most inimical to the plants submitted thereto. The admission of air, is a point which as far as I am aware, has never been effected in the manner represented in the sketch: it would be thus effected;--a series of apertures (_f_) should be provided at intervals along the front wall, which would externally be closed by small sliding shutters, and would communicate internally with a chamber (_g_) formed between the front wall and the side of the tank; this chamber would also communicate, by a series of openings, (_h_) with the interior space above the water in the tank, and from this space, through the covering of the tank, tubes (_m_), also placed at intervals, would be carried up through the soil, close to the side of the wall; these tubes should be furnished with caps or valves, so as so admit of the communication being stopped at any time. In applying this to the admission of air, we must not loose sight of a series of ventilators, (_i_), placed in the back wall of the house, which are of precisely the same nature and construction as the apertures (_f_), already spoken of. I shall have occasion hereafter, to notice the admission of air, but it will be well in this place, to explain the action of the plan proposed for that purpose: when it is judged that a change of the internal volume of air is requisite, the ventilators (_i_) are to be opened, which admits of a portion of the rarified air to pass off; the ventilators (_f_) are also to be opened, and by means of the action of these ventilators on each other, a portion of external air is taken in; this enters the chamber (_g_), which is warmed by its contiguity to the tank, and here becomes partially rarified, and rises to the top of the chamber; the apertures (_h_) admit it to the interior of the tank, where it becomes not only thoroughly warmed, but also imbibes a degree of moisture proportionate to the degree in which it becomes heated, and thence it enters the house by the tubes or shafts already spoken of. The advantages of warming and moistening the air thus admitted, are very important ones; for when either a cold or dry state, of the atmosphere prevails, its influence is very injurious to plants in these confined situations: cold raw air, when it comes in contact with the tender foliage of the plants, has the effect of chilling the sap in its progress through their tissue, and thus lessening their excitability, when it should be increased; whilst dry air acts as an incessant drain upon the vegetable juices, which it abstracts through the stomates and pores of the leaves and stems. When cold air is admitted to any position where it can unite with caloric, and not in an equal ratio with moisture, it necessarily becomes arid, and in that state it eagerly combines with moisture in any form with which it can come in contact therewith; and consequently if cold air is admitted to a plant structure, where it can have the means of combining with heat, faster than with moisture, it would be brought into this arid state, and would supply its voracious appetite, by abstracting the juices of the plant. It is a very important question how far this state of things is connected with many of the diseases as they are called, to which plants are subject; for my own part, I believe it to have a very considerable influence in the production of many of them. A shallow bed of soil (_k_), is all that would be required; for in the winter season, there is nothing gained by encouraging a very luxuriant and gross state of growth: the composition of this soil will be noticed hereafter: beneath it, and resting on the top of the tank, should be placed a layer of coarse open rubble, not less than six inches in thickness; and among this rubble by means of tubes (_n_), placed at intervals along the bed, I would occasionally pour considerable quantities of water, in order to maintain a due regulation of moisture in, and throughout the soil, among which the vapour arising from the water would ultimately rise. Beneath the tank a space (_o_), might be provided, which would serve admirably either for the cultivation of Mushrooms, or the forcing of Rhubarb, or Sea Kale. Transverse partitions should be introduced into the bed of soil, so as to divide the roots of each plant from those of its neighbours: this arrangement will admit of a complete succession of plants being maintained, by the removal of those which have become old and debilitated, and the substitution of young and vigorous ones; and this obstruction of the roots, will not be injurious, for the Cucumber does not by any means require to be permitted to extend its roots at random, but will readily submit itself to any rational regimen, with regard to the area from whence it is permitted to extract its food. A portion of soil sufficient to support one or two plants, could by this arrangement be renewed as occasion might require, and the roots of the contiguous plants would suffer no injury from the operation. The pathway of the house, should be paved so as to admit of its being occasionally washed and cleansed.

It will be found to be highly economical in reference to the consumption of fuel, to provide the structure with the means of being covered at night. Shutters of light frame-work, covered with any waterproof material, would be found to answer the purpose admirably; they should be elevated a few inches from the surface of the glass, and they should be arranged so as to confine a body of air, which acting as a very slow conductor of heat, would serve to prevent that incessant drain upon the temperature of the internal atmosphere, which takes place when the material employed is in contact with the glass, as well as when coverings are altogether absent. This would not be the only advantage, for as the covering would to a great extent prevent the radiation of heat from the internal atmosphere, so would it also prevent the necessity of the application of so powerful a degree of fire heat at night; and thus the plants would be permitted to enjoy that natural season of repose so essential to their well being, instead of being forced into growth by reason of a high temperature kept up, solely for the purpose of obviating the external cold.

CHAP. III.

ON THE PROPAGATION OF THE CUCUMBER.

Cucumbers are propagated by cuttings, by layers, and by seeds; the two former of these methods being frequently practised by those who have conveniences to keep their plants growing throughout the year; the latter being adopted either through choice or necessity, by the majority of cultivators, or those whose means will not enable them, even if they desired it, to keep up continually a successional growth.

Propagation by cuttings has many advantages to recommend it, especially when viewed in connection with the production of winter fruit. The plants raised by this mode of treatment, in comparison with those raised from seeds, are less gross and succulent in their nature, and more subdued in their manner of growth; whether it may be that having mature and perfectly formed parts, they are enabled to assimilate their food more rapidly, than young and imperfectly formed plants can do; or whether it is owing to any difference in the balance between the roots and leaves, which latter organs, in cuttings, and the former, in seedling plants, may be regarded as predominant, does not appear quite evident, probably the effect depends partly on each of these supposed causes. They are moreover, sooner in arriving at a fruit-bearing state, by reason of a universal natural law, by which the inflorescence and fructification of a plant becomes more general and perfect, in proportion as the plant attains proximity to its perfect developement; which effect, is owing to the more perfect elaboration and preparation of the materials, which when so prepared, furnish the means of perfecting the organs of reproduction. For the same reason, the operation of budding a portion of a seedling fruit tree, on a matured stem, is practised, in order to accelerate its fruitfulness; which result generally follows, in consequence of the difference existing in the nature of the food elaborated by the mature plant, and that deposited by one in an infant state. Thus it is also, that cuttings of flowering plants generally, are far sooner in arriving at a blooming state, than seedling plants of the same species: flowers and fruit being formed only by the aid of the perfectly elaborated sap; which is taken up into the system, and assimilated in the plant, in proportion to the number of healthy and mature leaves, in a full state of action: during the younger stages of growth, the crude material imbibed from the soil, is only partially elaborated, and in this state, is only converted into food suitable and destined to increase the foliaceous organs; but when these latter are in full and vigorous action, a supply of matter, not increased in quantity, but enriched in quality, becomes laid up in the store-house and structure of the plants; and it is by means of this matter, aided by the natural agents, that the nature of the developement is changed from being simply that of the organs of nutrition, to that of the more perfect and important organs of reproduction. Besides the precocity of plants propagated by cuttings, there is also another advantage resulting from the practice, and that is the preservation of particularly desirable varieties; the Cucumber is a plant which readily admits of hybridization, and although the result of this is sometimes to give rise to superior varieties, yet if impregnation is permitted to take place promiscuously, the bad qualities of particular varieties, are as likely to be combined in the succeeding race, as the good and desirable ones: this renders it important that the fruit which are preserved for seed, should have been carefully watched and protected when in blossom, from the reach of insects; which often effect the requisite union, in consequence of the pollen adhering to their bodies, and thus being brought into contact with the stigma. I need scarcely to say, that where only one variety is grown in any particular structure, the chances of admixture are less numerous.

The manner in which the operation of propagation by cutting is performed, is very simple: the tops of healthy growing shoots are taken off, at about two or three joints in length; they are then planted in deep pots, which are about half filled with light earth, such as decayed vegetable matter, and then covered by laying a piece of glass on the top of the pot; a simple and effective protection is thus formed, the sides of the pot acting as a partial shade, the glass admitting light sufficiently abundant to secure the action of the leaves, and maintaining a calm and moist atmosphere: the pots are to be plunged in a gentle bottom heat, and the cuttings will soon become rooted; after which they may be treated as established plants.

Propagation by layers, is another method similar to the last, of which it is a mere modification; and those points which mark the superiority of the one, are equally applicable in the case of the other. The operation may be performed in various ways: thus the branches may be layered at once into the soil, when these are trained close to its surface, and they will thus grow on with renewed vigour: when required for removal to other positions, they may be layered into pots of light soil, in doing which, a convenient branch may be brought down, secured firmly at a joint to the soil, and slightly covered therewith, when it will soon become rooted: another plan, is, to suspend in convenient places, pots having large holes beneath; through these holes, the points of growing shoots are introduced, and the pots having a little moss in the bottom, are then lightly filled with vegetable mould: they may also be propagated, by enveloping a joint of a growing shoot lightly with moss; the moss should be kept continually moist, and roots will soon be emitted into it, and when enough are produced, the plant may be detached.

Either of these methods of propagation will secure not only healthy, but fruitful plants, in a short space of time; and this latter point will be found to be one of no small advantage. The principal objection which may be urged against their adoption, is that they necessarily involve a process of transplantation, which under any circumstances, and however carefully performed, must be regarded as an evil rather than otherwise. It may be thought that the _check_ arising from transplantation may do good, by preventing too great luxuriance of growth, and thereby tending to accelerate fruitfulness; but even if this result may be apparently produced by such means, it is surely far more natural to check the plants, by withholding a portion of food, rather than by mutilating the organs by which their food is conveyed to them, and then actually placing them in a position where food is still more abundantly supplied than before. It is very questionable however, how far what is called a "check" is justifiable as a means of inducing fructification; for if fructification be the most perfect state at which a plant can arrive, there does not seem to be much rationality in adopting any such means as a "check" in bringing about this perfection of developement. A _check_ applied as a means of accelerating maturity, can only be regarded as an expedient, rendered necessary by previous defective treatment.

The most commonly practised as well as the most natural method of propagation, is by seeds, and this will generally be found to be also the best method, if the conditions required by its adoption can be properly carried out. There is however, one decided disadvantage attendant on the raising of Cucumber plants intended for winter forcing from seeds; and hence in a great measure arises the apparent superiority of propagating by extension: the disadvantage consists in the exceedingly succulent and lax nature of the tissue of the young plants; owing to that natural principle, by which their increase and extension is most especially provided for during the infant stages of their existence: the result is, that in consequence of the deficiency of light and solar heat, which are the grand agents of vegetable fructification, their sap does not become sufficiently elaborated, nor their tissue rendered sufficiently solid by assimilation and deposition of matter, to bring about the developement of floral parts; the food and moisture imbibed, instead of being sublimated and fully elaborated, is only partially acted on by the vital and natural agents, and the result is an increase of growth, but not a developement of fruit-bearing parts. There is nevertheless, an advantage in raising plants from seeds, not only as regards the obtaining of improved races, but also in a cultural point of view. The science of Horticulture, does acknowledge such a thing as progression, in the developement of plants; the functions of nutrition necessarily go on prior to those of reproduction or fructification, the latter being continually dependant on, as well as being the result of the former: hence we arrive at a conclusion, that _to supply uninterruptedly_, ALL _the elements which administer to the nutrition of a plant, is the most rational means of inducing a state of fruitfulness_. This may at first sight be questioned; cases may readily enough be quoted, in which food has been bountifully supplied, and the plants have grown amazingly, but not fruited; if however, food had been thus supplied, in connexion with a due share of _light_, and an _excess of heat_ had been avoided, we have natural evidence to prove unquestionably that fructification would have followed. An abundance of food, a high temperature, and a deficiency of light, are just the conditions which are opposed to the developement of the floral organs in plants, and are inductive of mere barren extension: not that plants grow thus, because they delight in such a state of things, but because they are thereby unnaturally excited and compelled to do so, although that growth cannot under such circumstances, become properly matured; and hence arises the impossibility of their producing blossoms.

The advantage of raising plants of Cucumbers from seeds, consists in the facility thus afforded of altogether avoiding transplantation: the roots of Cucumbers are of a very tender nature, and however carefully they may be transplanted, they are liable to sustain injury in the removal: by having recourse to depositing the seeds at once in the soil where they are intended to grow, this is entirely obviated, and there can be no possible reason why the conditions necessary to germination should not be as fully supplied in a hillock of soil, as when a portion of the soil is placed within a garden pot; this vessel can certainly have no influence in producing more perfect or healthy germination, whilst the mutilation of even the most careful act of transplantation, may tend to check the future developement of the plant.

It may be, however, that circumstances prevent the sowing of the seeds at once in their ultimate position, and in such cases, they may be sown singly in pots partly filled with decayed vegetable mould, plunged in a milk-warm bottom heat. The temperature both of the soil and atmosphere during this period, should not be high, but such as to permit the plants to push gradually forth from their dormitory, and assume by a natural process, the functions of active vitality. In order to maintain them in vigour of constitution, they should be exposed as much as possible to light; and that, by being placed near the glass, so as to receive the rays as little broken and refracted as possible. Water should not be applied at all, until vegetation has manifested itself, and afterwards, but sparingly, whilst the plants are young, especially in prolonged periods of dull sunless weather. Plants which are thus raised, should be planted out as soon as possible, when their fibres are least numerous, as a means of avoiding in part, the injuries to which they are exposed in transplantation.

When the plan of depositing the seeds in the hillock of soil is adopted, it is necessary to arrange the soil so that any subsequent additions made to it, may not have the effect of covering too deeply the roots of the plants, neither of burying the neck of the stem beneath the surface; it should be arranged so that this latter may remain elevated above the surrounding soil on the top of a slight mound, after the whole of the soil is adjusted for the roots. I have already mentioned that the depth of soil ought not to be at all considerable, but rather shallow than otherwise, so as to expose the roots as far as possible to the influence of the sun.

It will have been seen that the plan of raising young plants from seeds, has both its advantages and its disadvantages; and in order to avoid the latter, and secure some of the former, the seeds should be sown early in the autumn, whilst there is a sufficiency of heat and light, to mature the growth they make previous to the dull cheerless days which mark the near approach, and at length the arrival of winter. They will thus be endued with the "stamina" necessary to sustain them, through that trying period, and though not without difficulty, yet with comparative certainty, to reward the well-directed zeal of the cultivator. It is impossible to give any very minute directions as to the time of performing these operations of propagation, for like all other gardening operations, it is not at all requisite that they should be done on any particular day, nor ought they to be done except when natural conditions are favourable to success: from ten to twelve weeks generally elapse between the time of sowing the seeds and the production of fruit, according as the season may be favourable or otherwise.

The numerous hybrid varieties which are in cultivation, render it a matter of some importance to make choice of those most suitable to the purpose; these are however so continually changing, that it is useless to attempt a record of them. The Sion house Cucumber is perhaps the best of all suited for cultivation in the winter season. The principal features which are required in Cucumbers for winter forcing, are, precocity; compactness of growth, rather than luxuriance; prolificacy, rather than extreme length of fruit; and hardiness of constitution: these, are to the gardener far more important points, than those which entitle them to rank as "prize" varieties.

CHAP. IV.

ON THE TREATMENT OF THE MATURE PLANTS.

From the time that the plants become established, which is the period of their existence now about to be considered, they require to have the elements of vegetable growth duly supplied to them, in order to secure their successful developement. It is not enough to plant them in proper soil, and duly to water them, unless attention is also paid to the temperature, as well as the constituents of the atmosphere to which they are submitted; neither will attention to these latter points be sufficient to ensure success, if at the same time, the former are neglected. A _soil_ of suitable chemical, as well as mechanical composition, a pure and wholesome _atmosphere_, _water_ promptly and properly applied, and _heat_ duly regulated, are conditions which equally require minute care and attention in their adaptation; and these being applied upon the comprehensive, and perfectly harmonious principles of nature, will leave but little to be done in the shape of expedients, which are too frequently resorted to, as the means of counterbalancing either defective or unsuitable management. The application of these agents to the cultivation of the plant under consideration, in the winter season, will form the subjects of succeeding chapters. I will here briefly direct attention to the importance of light in the growth of plants, and then devote some space to the consideration of the subject of pruning and training.