The cool greenhouse may be said to cut at the root of the evil, for in it plants are grown and not manufactured, and long may it be before we give up the old-fashioned love for tending and training our favourites, until they become living friends, associated with all the joys and sorrows of our homes. Most people find out by bitter experience that plants grown at high-pressure speed in strong heat are unsuited to the conditions of a mere glass shelter, but, nevertheless, many of the same species, or their close allies, succeed admirably when brought up under more natural treatment, and are indispensable for pictorial grouping.
There is no question that in large conservatories detached from the dwelling, permanent planting of certain evergreen trees and shrubs is most advisable-a method already suggested on a small scale for one form of alpine house. These may be associated with well-planned rockwork, or fern-edged pool, so that the main features of the house may remain unaltered, while flowering plants can be brought in from the working-quarters according to season. The Himalayan House at Kew is a noble example, on a grand scale, of a cold conservatory of this character.
For such purposes, there is abundance of material in the way of fine-leaved shrubs of larger or smaller growth to suit all positions. Planting for continuance, however, must be done with the utmost care and good taste, or it will be disappointing. But this kind of planting is not always possible, nor even desirable, and many people, whether they will or no, have to content themselves with pot plants. In any case, a small space soon becomes overcrowded and untidy, and no plant is always at its best-two good reasons why, under limited conditions, permanent borders are better avoided, and every facility allowed for frequent rearrangement. This is more particularly the case when the ordinary small conservatory, which is seldom absent from the rectory or country home, or even the suburban villa, adjoins the sitting-rooms.
To this end, and for other reasons given in a former chapter, it is well also to dispense with fixed stages, using only such simple removable contrivances for the raising and arrangement of pots as may best lend themselves to the natural grouping of the plants at disposal.
In this way the whole rinse en scene of the conservatory can be altered at will, but it will be understood that this is intended merely as a practical suggestion to those who do not begrudge a little time and trouble to give a fresh setting of ordered beauty to the too rigid commonplace of ordinary daily life, and applies only to the drawing-room annexe, which is always in evidence.
The refreshment to mind and eye given by the varied plant pictures which a skilful hand is able to arrange can scarcely be told in words, but if one thinks of the ordinary greenhouse stage, with its serried ranks of flowering plants, flanked by brilliantly coloured Coleus and other variegated leafage, with here and there an Asparagus or Fern by way of foil, the difference may very readily be imagined. It has been said with reason that two-thirds of the available space in a greenhouse might well be allotted to flowerless plants.
But even with greenery the art of harmonious grouping depends in a great measure on the quick discrimination between concord and contrast. Sometimes the one, sometimes the other will give the best effect; but it is a mistake to think that foliage of any kind will accord with every flower.
The trained eye will detect in a moment the want of harmony, and hence the importance of having a good stock of the most varied greenery to choose from. It may be said in passing that one distinct advantage of the cold house system is that a much greater variety can be grown, as foliage plants not in use or any that are out of flower can be transferred to outdoor quarters or simple garden frames instead of either taking up precious room or perishing outright for lack of suitable accommodation.
For all purposes of grouping, then, greenery being indispensable, it will be well to make a note under the two heads lately defined of hardy and half-hardy plants of some of the most suitable for cold house culture.
The fashion of the day being to employ Palms of many kinds for decorative purposes, it is as well, perhaps, that we can, with confidence, place the two Fan Palms, Chamxrops excelsa and C. humilis, on the hardy list. They are much alike in general appearance, but the first-named is perhaps the best. It is a Chinese species, and is often met with under the alias of C. Fortunei, a fact to be noted.
The European Fan Palm (C. humilis) may be distinguished from it by the thorny projections on the leaf-stalks, the narrower plaits of its leaves, and by the offsets, which are thrown from the base of the stem. It is also somewhat dwarfer in growth.
Both are good stand-by plants, doing well out of doors during summer, but needing shelter from wind and draughts even more than frost in winter, as the broad leaves are easily torn and disfigured. Acanthus, so much more grown in pots as room- and basket-plants on the Continent than with us, should never be omitted. A. latifolius and A. spinosus are two distinct and useful species. Aralia sieboldi, another well-known evergreen, may be set down as indispensable.
Small plants of Muhlenbeckia, with foliage recalling the Maiden-hair Spleenwort, is desirable for many purposes. All sprays of it that have been used with cut flowers may be kept, and if they have not already begun to root in the water, may be given the benefit of a fresh jug to themselves, where they can complete the operation at their leisure. In due time several of the rooted sprays may be potted together and make pretty basket-plants. Perhaps others may have found no difficulty, but until the above method of striking cuttings of this graceful evergreen was accidentally discovered, I never once succeeded in rooting a plant of it by ordinary means.
The jug, which provides darkness for the rooting stems, is a point to be noted. Such minute details are very amateurish, but like an old cottage friend who always planted her cuttings of Lemon plant, in firm faith, under a Gooseberry bush, " I do believe there be sum'at in it !"
For mixing with spring bulbs, Solomon's Seal is one of the most charming of foliage plants. There should be a well prepared bed in some spare corner of the garden from which in the autumn the best roots can be taken for potting, the smaller tubers being replanted for the following year that they may have a season for recruiting.
The same advice may apply to most plants which have served their turn in the conservatory. Myrtles, large and small-leaved, and Eugenia buxifolia, provide good greenery of a different character. Eugenia will also bear its delicious fruit abundantly in a small-sized pot, making the greenhouse fragrant with its peculiar aromatic scent. Small-leaved Ivies can be used in various ways, and Senecio mikanoides, the Ivy-leaved Cape Groundsel, which may often be seen trailing half-wild over bushes in Cornwall, is by no means to be despised where a quick growing climber is desired. Amongst herbaceous plants, and therefore only of use during summer and autumn, Funkia grandiflora and Funkia sieboldiana are very ornamental, and particularly well adapted for grouping with various kinds of Lilies in flower.
Nothing of course can be more valuable than a well-grown stock of hardy evergreen Ferns, both native and foreign. Of these the British species of Maiden-hair (Adiantum CapillusVeneris), of which there are several remarkable varieties ; Polypody, especially the Welsh form ; Hart's-tongue ; Polystichum, with its proliferous forms ; and Asplenium Adiantum-nigrum (" French Fern "), may be mentioned. Of exotic species, Woodwardia radicans, with its massive drooping fronds, each carrying a bulblet at its point, is invaluable for large spaces. The Ostrich-plume Fern (Struthiopteris germanica), and Lomaria chilensis, and L. magellanica are also large-growing, handsome, and quite hardy.
Smaller species are Lastrxa marginata and Polystichum acrostichoides. Amongst deciduous species, the very beautiful plumose varieties of the lady Fern (Athyrium Filix-fcemina) are well worth growing, and the fine Canadian Maiden-hair (Adiantum pedatum) should not be overlooked. If variegated foliage be desired, the small Euonymus radicans and Aucubas are useful, and small tufts of the old-fashioned Ribbon grass, grown in pots, go well with various kinds of white Narcissi, and make a fair substitute for Eulalia zebrina and the variegated Carex japonica when these are not at hand, though both are good "grasses " for pot culture. Centaurea ragusina and Cineraria maritima will supply silvery foliage and come in well for lighting up a dark corner.