The Amateur's Greenhouse and Conservatory/Chapter 10
CHAPTER X.
HARD-WOODED GREENHOUSE PLANTS.
In this chapter we shall have to treat of a number of plants that differ wonderfully in constitution and requirements, and therefore it will be impossible to give any general directions for their cultivation on the plan of an introduction. A considerable proportion of them need abundance of light and air, and the more hardy of their number are impatient of artificial heat, and consequently must not be subjected to a high temperature in winter without due consideration of their ability to endure the trial. Not a few subjects in the list that follows require a practised hand and an experienced judgment for their successful management, and, as a rule, the cultivation of hard-wooded plants belongs to the higher range of horticultural practice.
Abutilon.—These are best adapted for training to pillars, but by a judicious system of pruning, bushy specimens may be produced, which will have a most effective appearance. In a young state the leading shoot will require stopping to encourage the production of side shoots, and in the following and subsequent winter seasons prune them to within two or three joints of the base of each shoot. By allowing the young shoots to grow unchecked and neatly tying them out, well-balanced specimens that will flower freely may be obtained in a comparatively short period. The green-leaved species such as A. striatum require a mixture of peat, loam, and leaf-mould, but for the variegated forms, as for example A. Thomsoni, fibrous peat and sand will be preferable. The young shoots taken off in the spring with a small heel strike freely, provided the cutting pots can be plunged in the cucumber or melon frame.
Acacias.—These may be divided into two classes, o comprising the comparatively small rigid growers, and represented by A. armata, and the other the more robust species, slender in growth and having feathery foliage, and represented by A. dealbata. Those of the first section may be propagated by means of cuttings, and can be kept in proper shape by pruning. The others are most readily propagated by seed, and must not be pruned so severely, especially after they have attained a large size. They all thrive in a mixture of peat, loam, and leaf-mould, or they may be grown in loam and leaf-mould alone.
The points of half-ripened shoots make the best cuttings, and therefore the summer season will be found the most suitable for increasing the stock of the small growing kinds. The spring is the proper time for sowing the seed, which should be soaked in warm water some time previously. Whether raised from cuttings or seeds, the young plants will require stopping once or twice after they are established in the small pots in which they are put when potted off singly, to induce them to produce an abundance of side shoots, and thus form a good foundation for bushy specimens. Acacias of all kinds require liberal supplies of water during the spring and summer, and at no season of the year must they suffer from an insufficiency of moisture at the roots. Should any of the specimens become infested with white scale, the best course will be to destroy them and commence with young plants from a clean stock, for it is impossible to thoroughly eradicate the pest when it has once become established. The time to prune is just previous to their commencing to make new growth. All the species may be grown in pots or be planted out in the conservatory border. Some of the robust growers, especially A. Riceana and A. dealbata, are very valuable for training over pillars and girders in large conservatories.
Adenandea.—A. fragans is a good plant. It has a naturally bushy habit, and the only special attention required is to tie out the shoots with the aid of neat stakes. The flowers are produced at the tips of last year's shoots. Peat and silver sand form the proper compost; and in shifting the plants into large pots it is of the highest importance to press the soil very firm. Careful watering is very essential at all seasons.
Aphelesis.—These require careful attention at all times, for if they suffer from neglect or bad management of any kind they quickly perish. They are propagated by means of cuttings; but the latter are difficult to strike, and the amateur will act wisely in purchasing thrifty plants in five-inch pots. Fibrous peat with which a moderate proportion of silver sand, and either small crocks or nodules of charcoal have been added, will be the most suitable compost to use. They must not be overpotted, and after they have grown into specimens a shift every second year will be sufficient to maintain them in a healthy state. Especial care must be taken to have the pots thoroughly clean, the draining perfect, the peat of the finest quality, and to press the soil with an equal degree of firmness all round the sides of the pot. A light airy position is essential to all seasons of the year, but more especially during the autumn and winter months. The soil must be maintained in a moderately moist condition at all times, and in the application of the water, care must be taken to ensure every portion of the ball being properly moistened, and no more must be applied until the soil has become rather dry again. The mode of growth will indicate the proper system of training, and this must be done some time during the winter. The flowers are produced at the points of the shoots, and when they begin to fade they should be removed by cutting them off, with a portion of the stem, just above the young shoots.
Boronias.—These are all of moderate growth, and with but a very small amount of trouble neat specimens may be produced. They require a mixture of two parts peat, one part fibrous loam, and a plentiful addition of sharp silver sand. They are propagated freely by means of cuttings, provided the points of short-jointed shoots are selected when the wood has become rather firm. They require a light airy position, and when employed in the decoration of the conservatory care must be taken to avoid putting them too far from the glass, or where they will not enjoy a fair share of air. They require the same care in watering and repotting as other delicate-rooted hard-wooded plants. It will be necessary to stop the young shoots once or twice when the plants are in a small state, but after they are shifted into five-inch pots the growth must be regulated with the aid of neat stakes,
Chorozemas.—These attractive plants are of free growth, and well-furnished specimens may be produced in a comparatively short space of time. A good stock may be propagated without difficulty, provided the small side shoots are selected for cuttings when moderately firm in the early part of the summer. Some of the species can be propagated by means of seed sown and otherwise managed as advised for acacias. Good fibrous peat two parts, mellow turfy loam one part, and a part of small crocks, nodules of charcoal, and silver sand, mixed together in equal proportions, will form a compost in which they make the most vigorous progress, and produce their flowers in the utmost profusion. They must not be overpotted even when in a young slate, and after they have attained a considerable size a shift once every second year will be ample. During the first year, and probably the second also, it will be necessary to pinch back the leading shoots once or twice to promote the production of side shoots. They are mostly of a straggling habit, and the training must be commenced at a very early period, and in each year this should be done during the autumn or winter, as they naturally flower early in the season, and it is difficult to train them properly after the flower-buds are formed without breaking off or otherwise injuring a portion of them. A light and airy position is of the first importance, especially when they are making their new growth; for if they are too far from the glass or crowded up with other plants, the wood will be thin and long-jointed, and in consequence they will flower unsatisfactorily the following season.
Correas.—These produce their flowers during the winter. They are neat in growth, and thrive in good fibrous peat and silver sand. They are propagated by grafts and cuttings. The points of the side-shoots make the best cuttings, and they should be taken when the wood has become rather firm. Unless the plants grow out of shape, which can be easily prevented, they will require very little pruning beyond the removal of a branch occasionally. During the summer season place them in the open air, to ensure the thorough maturation of the new
wood.
Crowea.— A peaty soil, moderate supplies of water, and a light position, are the main essentials to success in the cultivation of croweas. The short-jointed side shoots strike rather freely, provided they are taken when the wood is moderately firm, and the cuttings covered with a bell-glass. It is necessary to practise a judicious system of stopping when the plants are young, to ensure the production of bushy well-furnished specimens. They are exceedingly impatient of artificial heat.
Daphne.—The flowers of the greenhouse Daphnes are valued for bouquets during the winter season, for they are delightfully fragrant. Increasing the stock by cuttings is attended with such uncertainty that they are usually grafted upon D. laureola, which can be raised from seed. The seed is a long time in vegetating, and, considering the trouble attached to the grafting, amateurs will do well to procure healthy plants of a small size from a nursery. An open position out of doors during the summer season will benefit them, and if there is a probability of the flowers being required before the usual time, they may be placed in the early part of the winter in a temperature of about 55°; but, as they flower early in the new year, no forcing whatever is, as a rule, required.
Dillwynia.—A few of the species belonging to this genus are very interesting and attractive. They require fibrous peat to which a liberal proportion of silver sand has been added. After they have done flowering prune them back, and when they have fairly started into growth again place them in the open air. They must not be exposed to continuous rains, for if the soil remains for any length of time in a saturated state the young roots will perish.
Dracophyllum.—The pretty white-flowered Dracophyllum gracile is as useful for conservatory decoration as it is valuable in competitive groups. It should be potted in peat chopped up rather fine and mixed with a liberal quantity of silver sand. Specimens trained as bushes are more pleasing and effective than those trained to wire trellises. To produce these, stop the young shoots twice during the first two years after they are potted off singly. Afterwards the growth must be trained out nicely with the aid of neat stakes. As the flowers fade prune back the growth of the preceding season, and when the young shoots are an inch or so in length place the plants out of doors. They must not remain out of doors late in the autumn. It is advisable to keep them indoors altogether during wet summers. The points of the partly-matured shoot are the best for cuttings, but they do not strike freely.
Genetyllis.—These are remarkable for the distinct character of the flowers during the early spring months. A mixture consisting of three parts fibrous peat, one part turfy loam, and a liberal quantity of sand will form an excellent compost. They may be placed in the open air during the summer, but must be protected from heavy rains. After the necessary stopping of the young shoots during the first year or two, no pruning will be required unless from any cause the specimen suffers from neglect and grows out of shape.
Eriostemon.—These are valuable for the freedom with
ERIOSTEMON CUSPIDATUS.
Embothrium.—A splendid genus of nearly hardy shrubs adapted for the cool conservatory. The soil they require is a
EMBOTHRIUM COCCINEUM.
Erythrina.—When well grown the members of this genus are exceedingly attractive. They require a rich compost, and a mixture of two parts turfy loam and a part each of fibrous peat and well decayed manure suits them admirably. Towards the spring prune the shoots to within a short distance of the base, and when they afford an indication of starting into growth turn them out of the pots, remove the old soil and repot them. Soon after they have done flowering they will go to rest, and the water at this stage should be gradually lessened and finally withheld altogether, as the soil should be kept quite dry during the winter. The stock may be increased by taking off the young shoots when about three inches in length with a small heel, and inserting them round the sides of cutting pots filled with a light sandy compost. The cuttings strike more freely when the pots are plunged in a brisk bottom-heat. They require a moderate amount of pot-room and will receive much benefit when in full growth from liberal supplies of liquid manure.
Gompholobium.—The main essentials in the cultivation of these interesting plants are a light position, perfect drainage, and an open compost. The latter should be prepared by incorporating together equal parts turfy peat and loam, and liberal quantities of silver sand and nodules of charcoal. The species of a scandent habit will require a neat wire trellis for their support. They should be placed out of doors during the summer season, for the purpose of ensuring a thorough maturation of the young wood.
Grevilleas.—Generally grown for the graceful appearance of the foliage. They require a compost consisting of fibrous peat and loam and a moderate proportion of sand. An open position in the conservatory is necessary, and they may be placed out of doors in the summer. For the cool conservatory they are useful and interesting plants. G. alpestris with flowers red and yellow, and G. rosmarinifolia with red flowers are the two best, but a dozen or more good species may be found.
GREVILLEA ALPESTRlS.
Habrothamnus.—Owing to their robust habit, these are best adapted for training to pillars in large houses, but with care bush specimens may be produced. When grown as pot specimens it will be necessary to first form a foundation by stopping the young shoots once during the first year or two, and afterwards to prune early in the spring all the shoots back to within one or two buds of the base. They must be kept rather dry at the root when pruned, and as soon as they are fairly started into growth again turn them out of the pots, and after removing a portion of the old soil repot them in clean pots and a fresh compost. They will grow freely either in peat or loam, but the best compost for them is a mixture of peat, loam, and leaf-mould. When grown as bush specimens the shoots will require to be tied out, but when trained to a pillar or wall they should be allowed to grow in a natural manner.
Hebeclinium.—The chief value of these consists in their adaptability for winter decoration. They are all of comparatively rapid growth, and strong bushy specimens may be produced by the autumn from cuttings struck in the spring. If it is desired to keep the old plants, prune them rather severely, and afford them the assistance of a genial temperature and moist atmosphere until they have commenced to make new growth.
Hovea.—Like other hard-wooded plants of a similar character, these require an airy position in the greenhouse during the winter, and to be placed out of doors during the summer. A mixture of peat, loam, and sand forms a very excellent compost. The Hoveas are exceedingly valuable for the distinct colour of the flowers—namely, deep blue. They are well adapted for occupying prominent positions in competitive groups, although seldom seen at public exhibitions.
Labichea.—The only species grown, L. diversifolia, is well deserving of attention. The flowers are deep yellow and freely produced. A peaty soil is the most useful.
Lapageria.—Although a climber, the Lapageria is in every way suitable for growding in large pots and training to a balloon or similar-shaped trellis. Turfy loam and peat in equal parts, with a moderate proportion of small crocks, nodules of charcoal, and silver sand, form a very suitable compost. The drainage must be perfect, for during the summer season almost unlimited supplies of water will be required, and means must consequently be provided for the ready escape of superfluous moisture. If this is not done the soil will soon become sour and the roots will perish.
Leschenaultia.—Although more difficult to cultivate than a few other subjects, good specimens may be produced with ordinary care. They require an airy position near the glass during the winter, otherwise the tips of some of the young shoots will perish from the damp settling upon them. When placed out of doors during the summer, means must be adopted for their protection in case of heavy rains. They must also be taken indoors early in the autumn. They thrive in good fibrous peat chopped up rather fine and mixed with a liberal quantity of silver sand. Careful watering is essential, for they suffer severely if kept either too wet or too dry for any considerable period. Cuttings of the tops of young shoots when about half-ripe strike freely with the assistance of a mild bottom-heat and the protection of a bell-glass or propagating frame.
Leucopogon.—These all require much the same soil and management as the Epacris, but they do not require such hard pruning.
Lisianthus. These are rather difficult to manage, and a considerable amount of skill is necessary to produce large well-developed specimens. They are propagated by seed, which should be sown early in March. Sow on the top of the soil, and lay a flat piece of glass over the pot. When the young plants are large enough to handle, which will be in eight or ten weeks after they make their appearance above the surface, pot them off singly, and place them where they will receive the assistance of a genial bottom-heat. Here they should remain until the end of September, when they may be removed to the greenhouse, and placed in a warm corner. In March shift them into larger pots, and, if practicable, stand the pots upon a genial hotbed. Equal parts of loam and decayed manure, and two parts of peat, will, with the addition of a liberal quantity of sand, form excellent compost.
Macleana.—A compost consisting of equal parts of turfy loam and peat, well-drained pots, and moderate supplies of water are the main essentials of success in the cultivation of these plants. They do not require such a dry and airy position in the greenhouse as a few other subjects mentioned. Proper training must be practised from the first, as they are somewhat straggling in growth,
Nerium.—To have these in perfection they must be pruned carefully, have a season of rest annually, and be shifted once a year or be assisted with liquid manure. It is impossible to have satisfactory results when the plants are kept starving in the same put for several years and not pruned, shift them in the spring, and after they are well rooted water alternately with weak liquid manure. After they go out of bloom keep them rather dry at the roots for a short time, and then prune all the young shoots back to within two buds of the old wood. As the season will be advanced, assist them to start into growth quickly with the aid of a mild bottom-heat and the temperature of an intermediate house. To prevent the flowers been hidden with foliage, as is frequently the case, remove the shoots which start just below the flower-buds as soon as they begin to push. Besides hiding the flowers, they deprive them of a considerable share of support, and their removal is therefore of considerable importance. Good turfy loam three parts, peat one part, and well-decayed manure or leaf-mould one part, form a suitable compost.
Pimelea.—These deserve all the attention necessary to produce good plants. They may be propagated by means of cuttings when the new growth is partly ripe, but they are difficult to increase. Shift such as require that attention early in the spring, and after the flowers have faded place them out of doors to mature the young growth. The most suitable compost is prepared by mixing together three parts peat, one part loam, and half a part of silver sand.
Oxylobium.—There is nothing special in the cultivation of these interesting plants. They require sandy peat as a compost, well-drained pots, and a light and airy position in the greenhouse. They may be placed in the open air during the summer.
Serissa.—A small group of white flowering shrubs nearly hardy, and therefore valuable for cool houses. The soil should be sandy loam full of fibre or good peat. The best are S. multiplex, bearing double flowers, and S. fœtida foliis aureo-marginata, which is a very pretty plant in spite of its elongated name. These are well adapted for planting out in a border in an unheated conservatory, as they grow freely and take care of themselves. They are neat and lively plants, though not showy.
SERISSA FŒTIDA.
Thibaudia.—This is a genus of superbly fine flowering shrubs closely allied to Vaccinium. They require the same treatment
THIBAUDIA JESSICÆ.
Vaccinium.—A pretty group of heath-like plants, mostly hardy. We can select three beauties from the genus for the cool conservatory, where they will answer admirably to clothe
VACCINIUM SERPENS.
rock-work if planted in sandy peat in a light, airy, sunny place. Their names are V. leucostomum, with flowers scarlet and white, V. Rollisoni, flowers scarlet, and V. serpens, with elegant myrtle-like leaves and rich crimson flowers.