The glass-garden greenhouse
Under the somewhat clumsy name-for want of a better-. of the glass-garden it is intended to express the greenhouse adapted for the permanent planting of shrubs and climbers. It is, in fact, a garden in miniature, covered by glass, but requiring no interior furnishing, as of stands or stages, other than the plants themselves. The laying out of the beds, borders, and pathways must be controlled by the size of the structure and the kind of plants, be they shrubs or be they alpines, to be grown in it ; but while the main planting is permanent, it can and should be so arranged as to leave ample room for the introduction of successional plants. This, in outline, is the idea of the glass-garden ; and while it may be the most ambitious, it is, perhaps, also the most delightful, type of the cold greenhouse. Such a house may be of grand dimensions-an annexe, possibly, of one of the long ranges of glass-houses to be found in many a stately garden, constructed chiefly for the winter protection of flowering shrubs and bulbs, and for the purpose of giving interest and enjoyment, together with a certain amount of exercise, to those who are debarred from taking an active share in the more vigorous pursuits of healthy outdoor English life.
It stands to reason, to begin with, that the construction, as well as the planting, of such a winter garden requires both judgment and good taste, and will give ample scope for the exercise of a thorough knowledge of suitable subjects. Here, too, is a case in point, where a cold greenhouse may reasonably be fitted with a single or even double flow-and-return pipe, as required by the size of the building, in connection with the main boiler, but so furnished with valves as to shut off all heat, except when absolutely needful to keep out frost or to put the air in circulation to prevent stagnant damp. It is not hard to picture a grand glass-garden of this kind, large enough to give a permanent home to the flowering Acacias, Himalayan Rhododendrons, Boronias, Correas, and the like, which, though 'tender, live and flower profusely out of doors in sheltered positions in the favoured climate-for example, of the Isles of Scilly. It may be taken for granted that all shrubs and plants -and their name is legion-that will live happily in the open air in our southernmost counties are fit subjects to thrive well under the shelter of glass, assisted, in the hardest weather only, by just so much artificial heat as will suffice to prevent the thermometer falling below 35°.
Any of us who have had experience of the difference in well-doing between plants grown in pots and those which receive the more generous treatment of the greenhouse border will readily understand the advantages offered on this point by the glass-garden. Such a house should be under the charge of an exceptionally intelligent gardener, well instructed and interested in the cultivation of hardy and half-hardy plants, who will take a pride in making use of the heating apparatus as sparingly as possible. The idea, however, of a coalition between hardy plants and a glass shelter has hardly as yet permeated the minds of any but a few garden enthusiasts ; but this slur will not long be cast upon English gardens. Kew has taken the initiative in the costly and splendid new wing which has been added within the last few years to the Temperate range of glass-houses, and it is there we must go to learn what may be done on the grandest scale in the glass-garden. It is true that ample provision is there made for raising the temperature, but it is used only in case of need, and we come upon frequent mention of the " big unheated greenhouse " in notices of plants in flower in the Gardens. This covered-in garden, with its rare and lovely shrubs and exquisite Lilies, forms one of the most delightful attractions of Kew, which has so worthily earned, especially of late years, the appreciation and gratitude of all true garden lovers.
But we need not despair if, on the other hand, our winter garden must be of very modest character, and if our wish is to do without heating at all, even of the most temporary and removable kind. So be it. There is plenty of material at hand if one chooses without trespassing an inch upon dubitable ground, and quite as much pleasure and happiness to be gained in the use of it. I remember well the description of such a winter garden given in the pages of the Garden perhaps twenty years ago. In it there were neither hot-water pipes nor heating of any sort to get out of order and worry the contented owner, who was, nevertheless, under no great concern for his plants even in the midst of the hardest of black frosts, for he took care to grow only such as could pass through it unscathed, and who revelled in the fairest of spring bulbs and early flowers long before the open garden could boast of more than a chance blossom here and there. Very few - more's the pity - have been found to follow so good a lead and attain as great a reward.
The garden corridor greenhouse
The unheated greenhouse may take on occasion the form of a glass corridor, and when this happens to be a lean-to passageway connecting garden structures, or it may be outlying rooms of a dwelling, it is the place of all others in which to grow specimens of the rarer flowering shrubs, such as Carpenteria californica, which succeed best when trained against a wall, and which are all the better for having their root-room restricted by a narrow border. Sometimes a glass corridor may more conveniently have a span roof, as, for example, in cases where there is no carriage-way to the entrance of the house, and more or less distance has to be crossed in bad weather before reaching shelter.
A covered way, under such circumstances, though not in itself beautiful, is a boon to guests, and some method of making a simple glass-passage of the kind presentable at small expense is no less a boon sometimes to the host. There are plenty of hardy climbers of which use may be made, like the finer kinds of Clematis and Jasmines, of Ivy and of Vine, not to speak of Tea Roses, which are the glory of the cold-house gardener, while a corridor is a most fitting place for Agapanthus or Crinum Moorei, or any such grand but unwieldy plants, which are best grown in tubs or in Italian pottery of the massive sort. The only wonder is, with such wealth of fine and easily grown plants of every kind and habit at command, that our glass-houses should, even at this date, be so indifferently furnished as to variety, which the majority of them undoubtedly are.
But further discussion of suitable subjects for cold greenhouse treatment must be set aside for the present, and we must turn to the less ambitious types of glass-house, to be found in everybody's garden, which are mainly under the personal control of the owner, with or without the help of a gardener.
The conservatory greenhouse
There are two forms of glass-house common to the gardens of most country homes : the conservatory, which adjoins the dwelling, and into which one or more of the sitting-rooms generally open ; and the greenhouse, which finds its separate place, with more or less aptitude for its purpose, in the garden. Now, " conservatory " is a pretentious name, and it might be wished that one more modest could be coined to replace it ; but it would seem as if few folk were alive to the fact that conservatory and greenhouse are not convertible terms. Yet the difference between them is plain and well marked-a conservatory being a shelter where plants in flower may be shown and admired, while the greenhouse is the home and, at times, the hospital of plants in growth.
Where only one of these exists, doubtless there must be some adaptation to circumstances ; but it can scarcely be too much insisted on that the conservatory is not intended to be turned into a working greenhouse, as is too often done. If it must be, then I venture to urge that it is better to draw a curtain between sitting-room and the inevitable dishevelment of the garden workshop, and to let a cheerful bay-window, a glass porch, or any other convenient position receive the plants we have cherished, when they are ready to be displayed in their beauty. The conservatory, being, in fact, an ante-chamber or vestibule to the living-rooms of the house, should be, equally with these, always in good order. One of the first considerations, therefore, is to keep it clean.
This very trite assertion may provoke a jeer, but only those who have held the reins of management in their own hands can have any idea of the way in which debris of withered leaves and fallen flowers accumulate, to say nothing of evil pests in the shape of slugs and caterpillars, woodlice and centipedes, which stray in and hide under stages and in odd corners; and how important it is to keep clear of the unavoidable mustiness which comes of more or less perpetual damp. For this reason it is strongly to be recommended that a conservatory be used strictly for pot plants, that there should be no heavy fixed stages and no inside border for permanent planting of shrubs or climbers, in order that, at short intervals, the house may be emptied and thoroughly cleaned and rearranged. Stands or stages should be used mainly as aids in the grouping of plants, and the lighter and more unobtrusive and easily movable they are the better. These points are touched upon lightly here, for they must be reverted to later, and will very likely be regarded as fads ; but experience teaches. Cleanliness and good order, with fresh, healthy plants, well grouped and not always in the same stereotyped position, go far to make even a small conservatory not only the joy and pride of its owner but a pleasure to all who see it. A conservatory of this kind, however, necessitates some sort of separate and extra resource to act as feeder to it, and this may be found in cold frames or pits, or in a working greenhouse, from whence plants may be brought, and to which they can be returned when their flowering is over.
The working greenhouse
The ordinary span or lean-to greenhouse usually finds its place in some corner of the garden, and generally is-and ought to be-furnished with a front bench and some sort of stage. Dampness and a certain amount of " undress " here is not out of place. One's plants are in their nursery, or, it may be, recruiting ; pans of seedlings may stand about ; Ferns may be tucked away under the stage ; a Marechal Niel, with its roots in an inside border, or any other climbers one may desire, can be trained up the rafters or on the back-wall; and pruned back-plants, however shabby-looking, need not hide their diminished heads. What would be incongruous and unsightly in the conservatory is here natural and right. There is little, perhaps, to be said on so well-worn a theme for the present ; but certain points of construction, important to be considered in putting up any of the types of unheated glasshouses here spoken of, remain to be suggested.
Only this let me add. It is the working greenhouse that is 'the best of all -the sanctum sanctorum of the gardener. Who but those who know it can fathom the peace, the rest, the depth of happiness to be found within its hallowed precincts. What marvels of plant life open out there to the patient observer, what strange vagaries of the germination of seeds, what mysterious processes in the germination of Ferns ; what rare loveliness in the silent building up, leaf by leaf, of even the commonest plant ; what exquisite art in the gradual laying on of colours and moulding of buds and flowers ! Aye ! but treasures such as these are only unfolded to the vision of the devout lover who thinks no toil too great that will unlock the cabinet of Nature's secrets ; whose hand is not afraid to risk the roughness of daily tending ; whose ear is awake to whispers so low that they are unheeded by idle passers-by ; whose eye is quick to note the changes of an hour. Such reverent students learn to worship while they work, and to them, in the uplifting symbolism of Eastern speech, plants and flowers become, in very truth, as " the fringes of the garment of God."