PLATE III DENDROBIUM WARDIANUM (At the time the photograph was taken this plant bore 264 flowers.)PLATE IIIDENDROBIUM WARDIANUM(At the time the photograph was taken this plant bore 264 flowers.)
It is more in accordance with nature to grow epiphytal Orchids of convenient size in baskets to be suspended from the roof of the Orchid house, and in the case of subjects reputedly difficult to grow the best results are often attained in this way. At the same time, this is due as much to the plants being placed near to the glass of the roof, as to the fact that the air has better access to the roots than when the plants are in pots. Hence it is that for suspending plants of small and medium growth, Orchid pans made in the same way as the flower-pot are found to be a convenient substitute for baskets, as they are not so liable to decay as wood-baskets.
Stanhopeas, Lueddemannias, Acinetas, and some other Orchids which produce their flower spikes directly from the base of the growth, must be grown in baskets to admit of the proper production of their flowers, which, if grown in pots, are sent down into the compost and lost. Gongoras, Cirrhæas, and similar genera, which produce slender spikes of flowers of drooping habit, are also best in baskets, as they produce their flowers much more freely when the plants are suspended.
The Orchid pan, for suspending, is also equally good for Masdevallias of the Chimæra section, a large number of Bulbophyllums and Cirrhopetalums, and generally for plants of small stature which would be too far away from the glass if placed on the stage. For the bulk of the collection the grower has to use the ordinary flower-pots, which are still unsurpassed for general purposes. The elaborately designed pots, perforated with holes or slits, which were used for Orchids years ago, are not necessary, for there is no defect in the ordinary flower-pot which cannot be overcome by the careful and skilful practitioner.
Rafts and cylinders of teak-wood made in the same manner as baskets are useful for some species, but it has to be remembered that plants on rafts are liable to suffer from lack of sufficient moisture-holding material around them.Broughtonia sanguinea, however, is never so happy as whengrown on a horizontally suspended raft without the least potting material.
The great trouble with suspended Orchids, and one which precludes the cultivator employing this culture for so many plants as he could wish, is the drip they cause to the plants on the stages. No Orchid should have another plant suspended above it; if it is not possible to avoid this, the relative positions of the suspended plants should be changed as often as possible; water should only be given them by "dipping" the plants, and they should be allowed to drain thoroughly before being again suspended. As many of the suspended plants as possible should be arranged on each side of the path, and in other situations where there are no plants immediately under them.
Narrow rafts 4 inches wide and 1 foot or so in height are suitable forAngræcum infundibulare,A. imbricatum, and other scandent Angræcums of similar growth. These should be fastened to the rafts with some good Sphagnum-moss between the plant and the raft on the lower half, the base of the plant and the raft being afterwards fastened in a flower-pot with Sphagnum-moss, the raft leaning at a slight angle. Sphagnum-moss can be added on the upper part as the plant grows, and, when sufficiently rooted up the stem, it can be severed half-way up when the base will produce new growths.
Some years ago, when large specimens were favoured, it used to be the practice to stake or "stick" the plants, as it was called, some of them exhibiting almost as many sticks aspseudo-bulbs. The sticks rapidly decayed, often leaving the stumps to harbour fungus and cause injury to the plants.
The compact specimens of the present day, when properly grown, require no support from sticks. In respect to specimens of larger growth, such as Aërides of tall habit, Lælias of theL. purpurataclass, and Dendrobiums, when they require sticking at all, they may be securely supported by one stick in the centre, to which one of the strongest growths should be fastened, any others requiring support being looped to the centre stick. The fewer sticks used the better.
Dwarf plants with creeping rhizomes between the pseudo-bulbs used often to be secured when repotted by small wire pegs, and the custom is not yet quite obsolete. Metal, especially galvanised iron wire, which is most commonly used, is very injurious to any portion of an Orchid which is allowed to come in contact with it. Such pegs are unnecessary, for the plants can be fixed with the potting material, and later on the new roots will effectually secure them.
In fastening Orchids on rafts or blocks, fine copper wire should be used, and all the care possible taken to prevent it resting on the rhizomes or stems, a small piece of peat or Sphagnum-moss being placed beneath the wire where it crosses the plant. Where Orchids such as Phalænopsis are grown in baskets or hanging pans, the leaves should not be allowed to touch the wire suspenders, or injury will result. Where leaves too closely approach the wire suspenders during their growth, the wire should be bent to avoid contact, or have a smallshred of cotton-wool or other material bound round it at the point of contact, if the leaf cannot be drawn aside.
For staking Orchids, bamboo canes are preferable to common deal-wood sticks.
It adds much to the interest of a collection of Orchids, either small or large, if a proper system of recording the plants is arranged for by means of a stock-book, in which the name of each plant is entered as it is acquired, together with the source from which it was obtained, and any other particulars that may be required when the plant flowers. This entry need only be brief, and generally one, or at most two lines will suffice for each plant. If it is intended to keep the plants under numbers, the left-hand margin should bear consecutive numbers from one onward, but if it is desired to have the names on each plant, the names in the stock-book should be arranged in an alphabetical manner. In some collections where numbering is practised the number is written across the top of the label, and the name written lengthwise when desired.
The common deal label is not suitable, because the base soon decays in Orchid houses, causing danger from fungal growth, and rendering the identification of the plant after the label has perished, or fallen away, very uncertain. The lead number for clipping the rim of the pot, or attaching to the wires of the basket or suspending pan, is less objectionable, but they are only convenient where numbers are alone used. Zinc labels and various other contrivances have been tried, but the best and safestlabel, either for numbers or names, or both, is the white celluloid label, obtainable in all sizes, similar to the ordinary wooden plant label, and in the ticket form for attaching to the baskets by means of fine wire. This kind of label does not decay as the wood labels, and it may be cleaned and used again as long as it remains in a perfect condition. Let all labels be made as small as possible consistent with their being firmly fixed, as it detracts much from the appearance of a house of plants if the labels are too much in evidence. Care must be taken during repotting that the labels removed from the plants should each be returned to its proper specimen. Much trouble may be caused by mixing the labels.
An unsightly appearance is given to many collections of Orchids by the presence on some of the plants of a number of damaged or yellow leaves. These are often supposed to be the result of bad cultivation, and, in some cases, rightly so. But in all collections of Orchids the old leaves, even of the evergreen species, do not pass off naturally as they do in their native habitats, where they have the natural seasons with their climatic changes to cause the leaves to fall naturally. When cultivated under glass, the species which are known as evergreen kinds retain their old leaves long after they would have passed away in their native wilds; and not only that, but they decline and becomeunsightly for years under glass, instead of passing away in a few months. Consequently many Orchids in collections often carry at least twice as many leaves as they ought to do, and the oldest are the most unsightly. A ready example of this kind is given by most collections of Masdevallias. The leaves are usually densely packed, many of the older ones shabby, and not only unsightly in themselves, but interfering with the full development of the new growths.
Masdevallias have no developed pseudo-bulbs, but a joint will be seen where the leaf-blades join the basal stems; all damaged leaves should be cut off just above that joint, and it will be found that some of the plants will be benefited, both in appearance and condition, by having from one-third to one-half the number of their old and damaged leaves removed. The same remarks apply to all Orchids of similar growth, such as Pleurothallis and Octomerias, and indeed to the species generally, for damaged or decaying leaves can be of no assistance in the development of the plant, unless in exceptional cases where the grower must use his own discretion.
If an imported Orchid such as a Cattleya or Lælia, which has been cultivated under glass for several years and has many pseudo-bulbs, be turned out of the pot and the roots freed from the potting material, it will be seen that the new roots which nourish the plant are confined to the freshest pseudo-bulbs, and that the roots beneath the older pseudo-bulbs are in such a condition that they areuseless in the economy of the plant. This fact goes to show that the old pseudo-bulbs are being supported by the newer growths, and, that they are seriously impeding the full development of the flower-producing part of the specimen. In such cases it is a common thing to see large specimens collapse and die off, the decay being traceable to the old bulbs in the centre of the plant. It is, therefore, better to remove old pseudo-bulbs behind the last three or four leading ones, and, if it is desired to retain all leading portions of a large mass in one pot or pan to form a specimen, they should be potted together, when it will be found that, given reasonable treatment, they will make better specimens than if left in a mass. In the case of varieties that need to be propagated, the pieces removed should be placed in comparatively small Orchid pans or baskets, properly labelled, and in due time useful and often valuable specimens may be secured from material which would only have been detrimental to the parent plant. The same kind of treatment will be found equally beneficial in the case of garden hybrids which have been cultivated long enough to have a number of back bulbs. In such cases the plants frequently degenerate after the first two or three years, until they produce inferior flowers, but the removal of the back pseudo-bulbs results in giving the flowering growths the full benefit of the root action, and consequently the plants again produce flowers of good quality.
Potting time is a very convenient season to give special attention to the removal of useless leaves and pseudo-bulbs, as the plants can be readily handled when they are out of the pots.
All useless parts removed should be taken out of the house and burnt. It is a common practice to throw the leaves under the stage. No rubbish of this, or any other kind, should be allowed in the Orchid house, as it forms a harbour for insects and is, in other respects, objectionable.
It used to be thought a very delicate operation to divide an Orchid, or to remove any portion of it for the purpose of obtaining another specimen, and, when the operation was carried out, it was thought to be at the risk of the plant and its offset.
In the case of badly grown plants, or where the houses are unsuitable for growing Orchids successfully, there may still be considerable risk in the process; but under ordinary conditions, and where the plants have proper accommodation, there is no risk whatever; it may be said that plants are never in better health than when they are divided at reasonable intervals. If we consider the case ofCypripedium insigne Sanderæ, some of the white Cattleyas, and many other Orchids which were imported only as single specimens originally but which are now well represented in gardens, the advantage of dividing the plants is readily seen.
Pseudo-bulbous Orchids with progressive rhizomes, such as Cattleyas, Lælias, Oncidiums, and Odontoglossums, should be divided by severing the rhizomes, retaining twoor more pseudo-bulbs together. This operation can be done at any season of the year, but it is most convenient to do it at potting time, and, for preference, just before the commencement of the natural growing season of the plant. Small pieces should be placed in small Orchid pans or baskets, but larger ones may be potted at once and placed on the stage with the other plants.
Dendrobiums may also be propagated by dividing the plants, but a large section of the genus may also be propagated by cuttings of the pseudo-bulbs. This method is specially useful for increasing a rare and fine variety ofDendrobium nobileor others of the section, as a good supply of plants can quickly be obtained in this way. The method is to cut the pseudo-bulbs into lengths of two or three inches and to place them in small Orchid pans, six or eight in a pan, suspending the pan in a warm, moist, house. The Thunia section of Phaius,Epidendrum radicans, and some other Epidendrums and Orchids of similar growth may be multiplied in this manner. Further remarks on propagation will be found under the names of the genera enumerated.
Success or failure with any class of Orchids depends largely on the exercise of discretion in watering. While it may be said that more specimens are lost by having too little water, especially among the smaller-growing species,than by over-watering, at the same time much mischief is caused by a system of giving a little watering frequently all the year round, and without any regard to the period of growth or rest through which the plants are passing. Such treatment does not provide for strong growth during the growing season, or adequate rest after the growths are finished; consequently the plants decline in health and the flowers are not satisfactory. Rain-water is the only suitable water for Orchids, and the growers who can command a supply of it all the year round possess a great advantage over those who have to use water from any other source.
During the period of growth and root action, too much water at the root cannot easily be given, provided the material in which the plants are potted is sufficiently porous and the pots or Orchid pans have a sufficient drainage. The rule should be to water thoroughly when watering at all, making sure that the whole of the potting material is moistened well, then not to give more water to that plant until the effect of the watering is seen to be passing, the plant being still moist but approaching dryness, when the thorough watering should be repeated. Nothing is more misleading than to pour a little water each day on the surface of the material in which the plant is potted. This is often considered to be careful watering, but it results in a large number of the plants never getting thoroughly moist at the root, while others in a retentive compost, or where the drainage is defective, become soddened. Such cases may arise occasionally under any conditions, and, where a thoroughly dry plant is found at a season when it should be moist, it is better to plungethe pot or basket in water until it is perfectly soaked. In the case of a plant which is too wet with stagnant moisture, it should either be repotted after the wet potting material has been removed, or placed on a shelf to remain without water until it is again in a proper condition to receive it.
In all cases a spouted watering-pot should be used. The rose watering-pot and syringe are necessary things in the Orchid house, but the use of them should be rigidly restricted to some definite work, such as watering Orchids for the first time after repotting, sprinkling the floors, staging, and brick walls, and other work which cannot cause mischief. It used to be a common practice to water Orchids overhead with a rose watering-pot, but the plants so watered made but few roots, and the foliage was generally unsightly, owing to deposits from the water. It is therefore best to make a rule against watering overhead in a general way.
The syringe may be used among Dendrobiums and some other warm-house Orchids during the height of the growing season; but it would be safer to arrange for such work to be done by means of a sprayer and at shorter intervals. The sprayer is a very useful and beneficial contrivance, and, in the hands of a careful operator using clean rain-water, it affords a valuable aid in maintaining a healthily humid condition in the atmosphere of all the Orchid houses, especially during the heat of the summer.
Equal in importance to the giving of sufficient water during the growing season is the observance of the dry, resting season, which, in a varying degree, is required by all Orchids, whether they come from hot or cold habitats, and whether they are epiphytal or terrestrial species.
These, like the epiphytal Orchids, may be divided into two main classes, namely, those which lose their leaves annually, and those which are more or less evergreen. Some of the genera contain both of these classes, and notably the Calanthes. InC. vestita,C. Regnieri,C. rosea, and their varieties and hybrids the leaves turn yellow after the growths are fully made up, a sign which gives a good indication as to the necessity for withholding water for a lengthened period; whileCalanthe veratrifoliaand others of the class retain the last-made foliage green all the year round, the loss of foliage being in the old leaves, which should be removed at the first sign of decay. With these latter may be classed the Phaius, Zygopetalums, Cymbidiums, Cypripediums, and many others of evergreen habit, which require much care to be exercised in the matter of withholding water during the resting season, otherwise the plants will decline in vigour. After the growths are finished, most of these plants are benefited by removal to a cooler and more freely ventilated house for a few weeks, during which time the supply of water should be restricted, but they should never be allowed to suffer by being thoroughly dried. For Zygopetalums and other Orchids which it is customary to place in a rather drier atmosphere during the time they are in flower, such an interval would be sufficient rest.
It should be distinctly understood that, in the case of true epiphytes, there is no need for manures, and, that artificial chemical manures are almost certain to bring about disastrous results, the final collapse being in proportion to the potency of the stimulant used and the recklessness of the grower. Where rain-water can be obtained and stored for use throughout the season, it is safest and most satisfactory to rely on this alone, except for some terrestrial Orchids. The chief difficulty in recommending the use of manures for any class of plants, Orchids especially, is in the fact that, once the practice is commenced, even those cultivators who begin cautiously frequently lose discretion in the course of time and ruin their plants by excessive applications. It is for this reason that the growers of plants for market purposes, whose secret of success almost entirely depends on the use of manures, are careful to give out the supplies to the men who have to use them, or, with the very best intentions, they would often destroy a crop. Indeed, it is not uncommon for foremen, or men in charge of departments in large nurseries devoted to growing plants for market, to resort to unfair means to get extra supplies of manure for their plants, and frequently with bad results. There is another curious feature about the use of manures in market-plant gardens, namely, that all concerned observe the greatest secrecy in the matter, and rarely admit that theyuse "anything but water"—that being the common expression. The same secrecy is observed by the Orchid expert in most cases. Another thing is that there is no common formula accepted by all practitioners. Each seems to have his own opinions as to materials, quality, and strength of the stimulants used.
One thing is certain, that even where artificial manures are used, the time of application and its discontinuance has more to do with success or failure than the nature of the manure itself. Even in cases where the administration of a mild stimulant is of use during the period of active growth and free rooting, if the manure is not discontinued after growth is completed much mischief is done.
It is not necessary to go into the relative merits of chemical manures, which are not recommended for use, but it may be stated that some growers do use small quantities with apparently good results, restricting the use of the manure to the active growing season and during the time the flower-spikes are forming. Aërides, Saccolabiums, and Vandas seem to be exceptions, as they represent the highest development of the epiphyte. Odontoglossums and some similar Orchids have been treated to a very small quantity of Peruvian guano sprinkled in the water used for watering them in spring while the flowers were forming, and without a bad effect; but the quantity used was very small, and the water was not allowed to touch the leaves or pseudo-bulbs. One grower on the Continent was in the habit of sprinkling a handful of nitrate of soda in the gutter of the house, especially before, or during heavy rain, in order that a little solution of it might be carried into the rain-water tanks in the Orchid house. His plants throve well, and this shows that even with epiphytal Orchids there is a field open for experiment; but the operator must not lose sight of the fact that he is "playing with edged tools." We will now state what has been proved to be beneficial when carefully carried out. Those who grow batches of the showy Dendrobiums such asD. nobile,D. Wardianum,D. Phalænopsis, and others of the class, and who, at the growing season, place them in a warm, moist house, suspended from the roof for preference, frequently give them weak doses of liquid manure during the season of growth, and the plants make very fine growth.
PLATE IV CATTLEYA TRIANÆ Var. "Hydra" (The plant bore 88 flowers.)PLATE IVCATTLEYA TRIANÆVar. "Hydra"(The plant bore 88 flowers.)
The liquid from farm-yard manure, or from a stable, should be avoided, as its strength cannot be known; sometimes it is very weak, and at others fatally strong. A large tub with liquid manure made of cow-dung, and in which a coarse bag of soot has been sunk, is a safe manure for any plant, and if properly diluted can do no harm to plants requiring such a stimulant.
Terrestrial Orchids such as Calanthes and Phaius can scarcely be grown to their best without a liberal application of this, or some other manure known to the operator to be safe, during their season of growth. Cymbidiums, Zygopetalums, Peristerias, and other strong-growing Orchids have also been treated to weak liquid manure from the commencement of growth until the flowers expanded, with advantage so far as evidence is available.
An occasional watering of liquid manure, or slight sprinkling of guano, may be given beneath the staging in the evenings during the growing season.
The structure of the roots of Orchids does not favourthe idea that they are suited for taking up stimulating liquid in the manner common to fibrous-rooted plants.
On the general question of the use of stimulants in Orchid culture many clever men have carried out experiments. The late Dr. A. H. Smee went into the question, basing his experiments on the chemical constituents of the plants themselves, which is not an infallible guide.
The late Norman C. Cookson carefully studied the subject, and he recommended for experiment the following formula:—
Potassium nitrate (saltpetre),3 oz.Ammonium phosphate,2 oz.
Dissolve in a three-gallon jar of soft water, and when watering growing Orchids, or those perfecting their flowers, add one ounce of the solution to each gallon of water.
Again it must be urged that those experimenting with manures must do so only on growing plants, and when growth is completed it must be stopped. No Orchid grower should undertake such experiments without first obtaining his employer's concurrence.
Whilst we may definitely say that all Orchids require a resting season in some degree, the cultivator must be careful to arrange the resting season, in the matter of its duration and other particulars, in accordance with the nature of the plant, for in some classes of Orchids it is veryeasy to do much mischief by subjecting them to a too prolonged and rigorous resting time. Seedling Orchids, as a rule, require little or no resting season until after their first flowering, and Cattleyas, Læliocattleyas, and other evergreen hybrids require a rather shorter period of rest than deciduous species.
Bulbophyllums, Cirrhopetalums, and many other small-growing Orchids are frequently killed by attempting to give them a dry resting season, although there is a section which lose their leaves in winter like the deciduous Dendrobiums, and these are benefited by being dried off in a cooler house when the leaves fall, keeping them dry until growth starts again, in the same manner asDendrobium nobile,D. Wardianum,D. crassinode, and other deciduous Dendrobiums.
The evergreen Dendrobiums of theD. densiflorumandD. Farmericlass require a short rest in a lower temperature, and should be watered a little occasionally, especially if they show a tendency to shrivel, which is not a good thing for any Orchid.
Aërides, Vandas, and Saccolabiums require a lower temperature in winter, and less water. Many of these begin to grow in March; after that season they require heat and moisture more liberally.
As a rule, the plants themselves give the best indication when the resting season has arrived, and, in the case of those which lose their leaves, they show how much rest is necessary. The starting of the new growth indicates when growing conditions should be restored. In respect to the very small-growing species, and especially evergreen kinds, it is much better to ignore the resting season rather than to lower the vitality of the plants by a severe drying off.
While every plant in the collection should be given the best possible care and attention, it is advisable to keep the more rare and valuable specimens immediately under the eye of the grower. It is often the case that albinos, rare varieties, and new species are allowed to get mixed up in the general collection, and a plant that could not be replaced may be hidden by the commoner things which are not of so much consequence. In the case of the best spotted varieties ofOdontoglossum crispum, albino Cattleyas, and other exceptionally rare things, it is a good plan to arrange a batch of them together in the most suitable part of the house, or to place each on an inverted flower-pot at intervals along the staging, thus bringing them into prominence and facilitating the inspection of each at all times. Some use wire plant stands instead of inverted pots, but the moisture-holding flower-pots are preferable, if they are inspected occasionally to see that they are not harbouring insects. Albinos and fine varieties of Cattleyas and Lælias could be grown in suspended Orchid pans or baskets, to take them out of the general collection, and so grown they would make better progress than if placed on the stages. In the case of any plant not making satisfactory growth it is often beneficial to place it on an inverted pot to bring it more prominently under notice.
There is very much in the old-time advice, "Grow your plants clean," for a very large proportion of Orchid diseases and insect pests are due to errors in cultivation, more especially in the regulation of the temperature and the ventilation. Insanitary houses lower the vitality of the plants, and vegetation, like human beings, is a prey to disease when kept in unhealthy conditions.
Spot, or Orchid disease, exhibits itself in various forms. It is caused, as scientists say, by different micro-organisms, but in effect it is practically the same whether in the form known as "Spot," often seen in Phalænopsis, Aërides, and Vandas, or in the decayed and blackened pseudo-bulbs of Cattleyas, especiallyC. Warscewiczii(gigas), which from an apparently healthy plant may develop a diseased condition of the pseudo-bulbs, and become useless in a few days. In all such diseases it will be seen that the tissues have collapsed, the result being brown or blackish spots on leaves or bulbs. Imperfect nutrition from lack of healthy roots is a frequent cause of this mischief, for Aërides and Vandas which have been affected with "Spot" recover in the new growth, for a time at least, if a satisfactory root action can be set up.
Propagation, by freeing the recently made parts of the plants from the old and worn-out back portions, which are not furnished with the roots necessary to support themselvesis one of the best means of preventing Orchid diseases, and efforts should be made to keep the plants vigorous and, therefore, capable of resisting attacks by insect pests.
Plants are also benefited greatly by having their position in the houses changed, and that is one of the great advantages of the periodical inspection, for during this process the relative positions of the plants are altered.
It should be said that Cattleyas and other common Orchids badly affected by disease had better be burnt, for it is cheaper to buy a healthy young plant than to waste time in trying to bring the unsightly and diseased specimens back to health.
The Cattleya Fly (Isosoma orchidearum), first imported probably withCattleya Dowiana, and frequently with other Cattleyas since, affects the new growths, the grubs causing them to swell and rendering the growth useless. The same species, or one closely allied, also attacks the young roots of Cattleyas, Lælias, and their hybrids, causing unsightly galls on the points of the roots. Fumigation, with some safe preparation to destroy the fly, should be carried out, and every young growth and root-point as soon as they are seen to be affected should be cut off and burnt. By adopting these remedies it is possible to get rid of the pest. In purchasing freshly imported plants, care should be taken to reject those which show signs of having been affected by the fly.
Thrips, Red Spider, and Aphides occasionally appear in every collection, and the remedy is fumigation and sponging with an insecticide, which some growers prepare for themselves, either by pouring boiling water over coarse tobacco tied up in a cloth and adding a little soft soap, or bymaking an infusion of quassia chips. But excellent insecticides can be purchased already prepared, which are guaranteed to be safe and effective, and being of uniform strength, they may be used with confidence if the instructions given with the preparations are observed strictly.
Avoid using paraffin and emulsions of paraffin, for it is dangerous, not only to the plants sponged with it, but to all the plants in the house, for it affects the atmosphere.
These appear much less in collections now than formerly, because the old large specimens are replaced by young and vigorous plants. Thirty or forty years ago, it was a usual thing to spend several days every year scraping the brown scales from tall plants ofAërides odoratum,Vanda tricolor, and other specimen Orchids, and what was called "cleaning" was going on all the year round. Now there is much less need of such work, although scale will appear in its various species on one section of plants or another. In the periodical inspections, all plants attacked by it should have the insects removed by a piece of stick blunted at the edge and point, sponging the leaves afterwards with some diluted insecticide. Syringing with an insecticide, or dipping the plants in the liquid, should be avoided, for the quantity applied is likely to saturate the material in which the plants are potted and to run into the centres of the young growths and cause injury. By means of a sponge, it may be applied lightly or heavily, but the operator has command in each case over what he is doing.
Fortunately this pest is rare in Orchid houses, but when it appears it is easily destroyed in the same manner as scale.
The first of these insects to be noticed should be the signal for the laying of poison. Search should be made for the breeding quarters, which are often in the stoke-hole, or in some hot, dry corner of the house. Various preparations are recommended, but the best still seems to be the old phosphor paste, which should be placed on pieces of paper in the haunts of the insects in the evening, and removed the next morning, a fresh supply being put down every two or three days so long as one of the insects remains.
To combat these is more a question of diligence than anything else. The old remedies to attract them, such as lettuce leaves, or hollowed halves of potatoes, are still effective, and a walk round the houses with a light at night never goes unrewarded.
Whenever the time is to be spared, it is a good plan to overhaul one or other of the sections of Orchids thoroughly, and to have a more general inspection as soon as possible after the winter has passed, and at the end of the summer,this latter inspection being the more important. Cleanliness in everything around Orchids is one of the most important aids to successful culture, and, during the periodical inspections, plants which are not clean should be cleansed, their pots where it is required washed, and the staging and any part of the house requiring it thoroughly cleansed before the plants are rearranged. During the course of the work certain plants which would be benefited by being repotted, or divided, will be found, and these should be given attention. The water in the tub in which the green deposit on the pots has been removed by scrubbing, and as much of the other water used in cleansing as can be dealt with, should be poured down a drain outside the Orchid house. If thrown on the floor of the house, it leaves an unpleasant odour, which is harmful and lasts a long time.
During the inspection at the end of the summer the staging should be repaired where necessary, the heating apparatus carefully overhauled and defects made good, in order to minimise the risk of having to do the work during the cold weather. Where it is deemed advisable to black the hot-water piping, use only lamp-black and oil. Paint gives off injurious gases for a considerable time, and where persons have been incautious enough to use gas-tar the most lamentable results have followed, the mischief lasting for years. These periodical inspections and rearrangement of the plants are also useful in preventing the same plants occupying the same positions for too long a time. A change of position in the house is beneficial, even where the plants are not crowded; but in collections where the plants are closely arranged, to change their positions frequently,goes far to mitigate the evil arising from want of space. In preparing for a thorough inspection of the plants in a house, it is desirable to remove a number of the plants to another house to make room to examine the rest without risk of breakage, the plants removed at the commencement being returned to fill the space remaining after the work has been completed.
The Orchid grower is always supposed to have the plants under his direct inspection and to treat them with individual care, but these occasional reviews often reveal defects in some of the specimens which would otherwise have escaped for some considerable time.
There are many dwelling-houses of moderate pretensions, especially in towns and suburban districts, in which the sole accommodation for plant-growing consists of the conservatory adjoining the house, and this is, in most cases, heated by one or other of the simple means at command for the purpose. The contents of such structures are usually unsatisfactory, the Pelargoniums, Fuchsias, and other soft-wooded plants which are arranged with some of the hardier Palms and Ferns being drawn into spindly growth, which results in a miserable supply of flowers for a short season, and afterwards in decaying foliage, which is not ornamental. Quite a new interest would open up tothe owners of such places were they to turn their attention to acquiring from time to time a few of the Orchids which are now to be procured as cheaply as the less suitable plants, such as Pelargoniums. Already some successes have been recorded in this direction.
Let us consider the different classes of conservatories, and the species most likely to succeed in them.
To take first the commonest kind of small conservatory attached to villa gardens. These are unheated structures except in the winter months, when the temperature cannot be kept from getting below 45° Fahr. without the aid of one of the oil-stove heating apparatus, or heat turned on from the pipe connected with the kitchen range, where arrangements for doing so have been provided. These means of applying artificial heat should be used as little as possible, and only to prevent the temperature falling below 45° Fahr., for in confined spaces and with such means of heating, the atmosphere is better for the plants without the use of artificial heat, whenever the house can be kept from getting too cold without it. In such conservatories, many of the Odontoglossums, Masdevallias,Oncidium varicosum,O. crispum,O. prætextum,O. Gardneri, the pretty scarletSophronitis grandiflora,Epidendrum vitellinum,Lycaste Skinneri,Cypripedium insigne,Disa grandiflora, and a number of other pretty and inexpensive species can be grown satisfactorily, especially if the Oncidiums, Sophronitis,Odontoglossum Rossii majus, and other of the smaller species be placed in baskets for suspending, a means of cultivation which suits them best, and adds to their decorative effect.
The next step is the larger conservatory adjoiningmany town and suburban dwellings. These are heated by a small boiler with hot-water pipes, a means, it should be said, which is the only satisfactory method of heating glass structures. To the species indicated for the smaller and less safely heated structures may be added a very wide range of subjects of great beauty. In such a structure the Palms supplying decorative foliage may be much restricted, or entirely dispensed with, asCymbidium Lowianum,C. giganteum,C. Tracyanum, and any others of the section having evergreen leaves of much grace, are decorative plants at all seasons, and possess the further advantage of being furnished with fine spikes of flowers for several months in the year. These large and strong-growing species are specially adapted for the conservatory, an Orchid house being unnecessary for them.
To the heated conservatory also may now be handed over the showier species and hybrids of the South American Cypripediums (Selenipediums), which, probably because of their very free-growing nature rendering them too large for the Orchid house, and the ready manner in which they may be increased, have caused them to be slighted lately by growers of collections of Orchids. The air of the conservatory, rather drier than that of the Orchid house, suits these plants admirably. Their bright evergreen foliage and tall sprays of white and rose, or greenish flowers tinged with purple, which often by succession keep the specimens in bloom for six months in the year, render them beautiful and interesting subjects for the conservatory.
The strongest and best kinds to be acquired areSelenipedium longifolium,S. Sedenii,S. cardinale,S. calurum,S. grande,S. Schröderæ, andS. albo-purpureum.
Cypriperium Charlesworthii,C. Spicerianum, andC. Leeanumshould also be added. The larger, heated conservatories might well be furnished with the Orchids recommended rather than the plants generally used for decorating them, for these have to be changed frequently. The Orchids, if carefully tended, will grow permanently in the conservatory and be a source of never-failing interest. In these large conservatories, Stanhopeas in baskets for suspending are ornamental plants, and Sobralias on the floor or central bed would prove satisfactory. To those enumerated many more might be added, but in all cases it is best to get only evergreen kinds, which may be grown continuously in the same house.
Orchids having flowers with persistent perianths, in which the segments do not drop as in many other flowers, are of the highest value for cut flowers, as some or other of them can be obtained in every month in the year. Large quantities of the large-flowered Cattleyas, especiallyC. labiata, ofC. Harrisonianaand its near allyC. Loddigesii,Odontoglossum crispum,O. Pescatorei, Dendrobiums, and other showy Orchids are grown for cut flowers in nurseries where Orchids are not required for other than market purposes. In many private gardens, also, the same kinds of Orchids are grown for decorative purposes, even withouta desire to grow a general collection. Those who arrange for a general collection of Orchids as their primary object often cut the flowers for their own use, or to give to their friends, and the following remarks may be useful to all classes of growers.
A large proportion of the flowers of Orchids used for decorative purposes are in a great degree wasted by being cut in an immature state soon after the buds have expanded. Such flowers last but a very short time, and, if used for decoration by night, are only presentable for one evening. Orchid flowers should not be cut until they are fully mature and their tissues hardened. They last longer even if they are cut after they are past their best, than they do if cut too soon after expanding. When mature, the flowers require less support from moisture passing up the stem than most flowers, but if cut in an undeveloped state sufficient moisture cannot be obtained through the stems, even if well supplied with water, to continue the development, and the petals droop and the flowers soon wither.