The case which I have long had in use was originally made with a water-tank to be heated by a lamp burning beneath it, but any artificial heating was dispensed with years ago. All that is needed is a removable zinc tray, about 2 in. deep, to hold a layer of damp sand on which the pots can stand. It is, in fact, a mere glass-box with a sloping lid, standing on legs of a convenient height, which may be made by any one who is capable of handling carpentering tools.
This most useful piece of furniture can generally find a place in some unoccupied corner of a greenhouse-preferably, of course, in a working greenhouse, as it is not ornamental-and is then always ready to take in a pot of cuttings or of seed, and is invaluable all the year round. Seed-sowing is not merely a springtide occupation. In almost every case seeds vegetate more surely and freely when they are sown as soon as ripe, though some are benefited by a short time of waiting to harden and consolidate.
The seeds of Primulas, Anemones, Gentians, and many other plants will germinate at once if sown as soon as they are gathered, but if they are held over till the spring a few may come up, but it is quite possible that there may be no crop of seedlings until the following year-not because the seed is bad, but because the vitality is in some degree lowered.
For this reason, it is not wise to discard any pan containing valuable seed, without giving it the chance of germinating the following year. This may seem a formidable trial of patience, but I have done it many times and with success. Seeds should, therefore, be not only collected, but sown, as soon as they are fit. Another point to remember is that seeds can scarcely be sown too thinly. It is much better to have a few strong plants than dozens of spindlings elbowing themselves out of the seed-pan and driving the raiser distracted from inability to cope with them.
Nature is prodigal in the matter of seed-sowing, but she thoroughly understands the principle of the survival of the fittest, and prepares for it in her seemingly rough and ready way. Under cultivation, lavishness of this kind is mere waste of life. Nothing is more fascinating than to watch the germination and progress of seedlings, from the unfolding of the cotyledons, through the processes of pricking-out and shifting into pots of graduated size, until, after due education in the way of training and trimming into shape, they grow into fine specimen plants. The same may be said of cuttings.
The little slip that one begs of a kindly neighbour and which responds to care by rooting and thriving gives an infinity of pleasure by association and by pride of skill. It is here that the bell-glasses come in as valuable auxiliaries. A cutting has twice the chance of striking if it be kept " close," as it is then sheltered from trying variations of temperature, for its well-doing depends largely on the leaves never losing their freshness and remaining as far as may be in workable order. It may-possibly-recover if put in water to revive after it has become limp, and do well, but it is safer far, seeing that its leaves are its lungs, never to let a cutting flag, so that there may be no interference with the work of forming a callus.
This term is applied to the granulation of the tissues at the base of the cutting, and shows that healthy action is going on, which will soon be followed by roots. As a rule, a cutting will root much more rapidly under a bell-glass, but the close treatment does not answer in every case.
A pelargonium, for example, roots much more freely in full exposure to sun and light, and would suffer from the damp still air of the bell-glass. It is very necessary, in all cases, to lift the glasses at least once a day to wipe off the condensed moisture within them, otherwise the cuttings are apt to "damp off." It is difficult to give any very definite rules as to the uses of bell-glasses. Failure is probably due, when it occurs, to the cuttings being in an unfit state to strike, but they are, when properly used, indispensable additions to the amateur's garden outfit. It is well always to remember the old garden adage that " In spring you may bid your cutting to grow, but in autumn it must be asked."
The training and pruning of pot plants are arts which must be learnt by practice. The amateur seldom has courage to use the knife as much as he should, but the beauty and symmetry of most plants depend upon the treatment they receive on this point. Many kinds, both of seedlings and cuttings, have to be pinched back at an early stage to induce bushy growth, otherwise they may run up with a bare unsightly stem. If they are allowed to go ahead at their own sweet will, it is a difficult matter to bring them back, later on, into good shape.
The time at which pruning is done is also of great importance. Too often the cutting back of a plant or shrub is neglected at the right moment-then, in a fit of energy and ignorance, we set to work and find, too late, that we have diligently cut away every hope of flowers for the coming season. Deutzias flower on the young wood, and any cutting away that is needed of the old branches should be done immediately after flowering.
Clematises may be taken as another familiar example. The purple C. Jackmani flowers in the autumn on the new growth of the current year, and requires pruning back during winter before the shoots begin to break. C. montana, 'as well as those of the large earlier-flowering type (like C. lanuginosa), bloom, on the contrary, on the wood of the last season, and merely need thinning out, or must be cut back very sparingly when flowering is over. The same rule applies to the charming, half-hardy New Zealand species, C. indivisa. Many of the fine hybrid forms of Clematis succeed well, not as climbers, but in small pots, and are particularly well adapted for an unheated greenhouse.
Roses on their own roots of the less vigorous type, such as Catherine Mermet, are often sufficiently pruned by cutting their flowers with a tolerably long stem, whereas stronger-growers are the better for harder cutting back. A few shrubs, like Brugmansia and Desmodium, will bear cutting down to the ground level after flowering, and succeed all the better for such drastic treatment.
is one of the most critical operations of greenhouse work, requiring both knowledge and judgment. The plan of going round with a watering-pot and giving a driblet to every plant, whether it wants it or not, is most injurious.
Many a time it happens when leaves are noticed to be flagging that more water is given, when in reality the soil is saturated and the plant is already suffering from over-doses which it has not the power to assimilate. In potting, sufficient space should be allowed below the rim of the pot to hold water. In hot, dry weather this space may have to be filled up two, or even three, times, in order that the soil maybe thoroughly moistened-especially when the potting has been as firm as it should be-after which it will probably need no more for a day or two.
Arums, being water-plants, are all the better for standing in a pan of water during growth, and a drop hanging from the point of the leaf is a sign of perfect health. Heaths, though they must never once be allowed to become dust-dry, will not bear sodden, water-logged soil, which will decay the fine root-fibres, and it is a matter of experience to keep the happy mean.
Succulent plants, on the other hand, must be kept dry rather than moist, and in winter, as a general rule, require no water at all, unless they show signs of distress by becoming shrivelled. Almost all plants, however, during their growing season, will take ample supplies, because it must be remembered that all food reaches them in liquid form. When active growth begins to lessen and life shows signs of ebbing, it is better gradually to withhold water.
Bulbs, especially those which lose their leaves, require a season of complete rest, and usually have to be kept dry. Cape bulbs, like Nerines and some others, as before, said, enjoy a few weeks of roasting on a sunny shelf or frame-the pots being turned on their sides, the more surely to be safe from drip-and bloom all the better for it.
Scarborough Lilies (Vallota purpurea), on the contrary, being more or less evergreen, must be kept growing all the year round. The drying-off system, though admirable in many cases, does not always answer-a fact which has been proved with regard to Cyclamens, which formerly used to be so treated. I had a fine Persian Cyclamen for many years, treasured in memory of a friend, which literally gave hundreds of flowers every season.
The corm was re-potted immediately after the blooming was over, and the pot sunk in a bed of hotbed refuse prepared for plants which were benefited by such treatment and kept watered. The old leaves soon disappeared, new ones taking their place almost at once, and nothing could have been more satisfactory than the result.
When I see it stated, as I often do, that two-year-old corms of Cyclamen are of little value, fit only for the rubbish-heap, I call to mind my ancient comrade who fought the battle of life for many years so bravely, and sigh to think of the waste of good plants which, with a little care, might give delight to many who cannot afford the luxury of buying them.
A brass syringe is a very useful help in watering-a shower overhead being both refreshing and cleansing to most plants, and t terror to red spider. Ferns, however, and more particularly Maidenhairs, though they love a damp atmosphere about them, are not improved by having their fronds wetted. In truth, there is scarcely any part of greenhouse work which has to be learnt by experience so much as watering. Yet, oddly enough, in the absence of the rightful owner the watering-pot is generally entrusted with a light heart to any one willing to undertake the office of using it, without a thought of Nemesis.
A word may here be said on the use of Insecticides. In an unheated greenhouse there should be little occasion for such applications. Blight of all kinds, especially mealy-bug and scale, naturally grow apace in the warmth and close atmosphere of the hot-house, but ought never to be found where there is no artificial heat.
Green fly and thrips are sometimes troublesome, but a very little watchfulness and attention will suffice to keep them under, and prevention is better than cure. In a small greenhouse, a basin with a decoction of quassia-chips, or even of plain water, and a small paint-brush always at hand in use will keep the enemy at bay.
On a larger scale, fumigation occasionally will be necessary. When plants are growing vigorously, there is little to fear from insect pests, and towards this desirable end some kind of artificial manure or plant food is often a great help, such as bone meal-in certain cases to be mixed with the soil in potting-or one of the many specialities advertised for the purpose.
Soot-water, made by putting a coarse canvas bag containing a peck of soot into a barrel of rain-water and letting it stand, after an occasional stir, until the liquid is of the colour of strong tea and quite clear from sediment, is one of the most valuable of fertilisers that can be used, and may be safely given to Ferns as well as to flowering plants. It should be diluted with rain-water when used, and given twice a week during the growing- and flowering-period-a much better plan than administering a strong dose haphazard. Stimulants of all kinds must naturally be discontinued when plants are at rest.
A garden-book in which entries are regularly made of plants received and from whence they come, with accurate dates of seeds sown and of their germination, with all other details of the kind which may strike the cultivator as being noteworthy, helps to lift the routine of greenhouse work out of the rut of mere commonplace, and makes it at once more systematic and scientific. Such a record faithfully kept, besides adding tenfold to our interest, increases in value year by year, and can confidently be appealed to for the settlement of doubtful questions which continually crop up.
It is a happy thing to have a working greenhouse of our very own where we may find occupation, not in desultory fashion, but with method and intent, and even make mistakes at our own sweet will. In doing so we learn by experiment the intricacies and the art as well as the delights of plant-management, which neither gardener nor printed book can teach so well as the practice of our own hands-so true is it that one grain of experience is worth a whole bushel of theory.
The unheated greenhouse has a future before it full of possibilities, while on its experimental side there is a vast amount yet for the most skilful to learn. On a large scale, it is worthy of a palace, but like all other phases of garden-work it belongs to no class and adapts itself to every home, bringing beauty and solace as much into leisured as into toiling lives as scarcely any other recreative occupation can.
The trend of modern out-door gardening is towards broad effects, grand vistas, spreading lawns, and cascades of roses-in short, towards all the garden luxury which lies within the scope of ample space and riches at command-delightful beyond words for those who can indulge in them.
The unheated greenhouse, while it appeals to these, for it may take on noblest proportions, appeals first and foremost to the plant votary of another calibre and to a different sense. It is within the compass, if need be, of moderate means and moderate powers of health and strength, providing a calm and restful, yet sufficiently absorbing, recreation at all times from the arduous duties, or, it may be, labours of life, whereby the simplest home and family festival may be glorified-or the hours of harass and sorrow mitigated and soothed, while the tension of anxious care is relaxed.
The earnest wish of my heart will be fulfilled if these practical hints, slightly, but not, I hope, carelessly, strung together, may awaken greater interest in a branch of garden-work which, for some special reasons, is beyond all others suited to rest the weary brain without over-taxing a not too robust physique.