# The Amateur's Greenhouse and Conservatory/Chapter 7

CHAPTER VII.
SOFT-WOODED GREENHOUSE PLANTS.
Between herbaceous and soft-wooded plants the difference is sufficiently decisive, but as to cultivation, they require pretty nearly the same conditions, and may, therefore, be associated in the same house. We shall in this chapter ofter brief directions for the cultivation of soft-wooded plants, but reserve for separate chapters the pelargonium and the fuchsia, on account of their great importance. The whole of the plants now before us may be raised from seeds or cuttings, and, as a rule, the latter are to be preferred. If one or two hard-wooded plants should find their way into this list it will be because they associate better with the softer section than with that to which a technical classification would assign them.
Bouvardia.—These are hard-wooded plants, but associate best with soft-wooded plants, and should only be grown in a house that is kept well heated during winter. Those employed for bedding purposes make nice pot plants, but the best of the family is B. longiflora, which produces a profusion of most elegant and sweet-scented white flowers during the winter. It is a troublesome plant, but worth any amount of trouble. Strike cuttings of the young wood in a brisk moist heat in March. Pot off as soon as rooted in five-inch pots, in a mixture of equal parts loam and peat, and a sixth part of the whole bulk of silver sand. Put them into the warmest place you have, but they must not be closely shut up, and the foliage must be frequently syringed. A fortnight after this potting pinch out the points of all the shoots to promote a bushy habit. Winter them in a temperature of 50', and in February shift them into eight-inch pots, and after this potting put them in a good
BOUVARDIA LONGIFLORA.
​growing temperature, and as the season advances move them to cooler quarters, so that by the middle of August they may be in a light airy house, to ripen the wood and prepare them for flowering. As soon as flowers appear put them into a temperature of 60°, keep them very clean, and they will continue to flower for four or five months.
The bedding varieties of bouvardia are more hardy than the lovely longiflora, and may be prepared for the embellishment of the conservatory by a very simple course of culture. In the middle of May secure a sufficient number of plants of the sorts required. Newly-made plants from spring cuttings will not do, but old scrubby ugly ones will answer perfectly. Cut them rather close, so that when they make new shoots they will become neat round bushes, and plant them out in a sunny spot. Give water as required. In the first or second week of July pinch out the points of all shoots, and give no more water. About the middle of September take them up carefully, and pot them in a light loamy mixture, taking care to injure the roots as little as possible. Give them a good watering, and then put them near a wall out of doors where the sun will not shine on them, and keep them regularly sprinkled and watered. In the early part of October take them into the greenhouse, and very soon they will begin to flower and make a splendid show. B. Vreelanda, which is a capital bedding plant, is also one of the best for this rough-and-ready course of culture for the production of winter flowers.
Bouvardias may be easily multiplied by root-cuttings, and those intended for flowering in summer may be wintered in a temperature of 40° to 50°.
Cytisus.—The pretty greenhouse brooms are so easy to manage that we may dispose of them in a few words. They may be raised from seed without difficulty, but it requires some experience to raise them from cuttings. The best soil for them is a mixture of peat and loam, with a sixth part sand. Though almost hardy, they like warmth and a moist atmosphere when growing. When they become fair-sized trees they will bear rough treatment without harm, and may be wintered in a cool house, provided they are never touched by frost. When they are large enough to be in eight-inch pots they may remain in the same pots for several years if assisted with weak manure water in the early summer when making their ​new growth. If required to flower in winter treat as recommended for bouvardias.
Cheieanthus.—The Double Wallflowers are to be valued for the conservatory, and they may, in the course of years, be grown to a large size in the form of noble trees. For all ordinary purposes two-year old plants are the most suitable. The cuttings are struck under a hand-glass as soon as they can be had, and when nicely rooted are planted out at a distance of nine inches apart, in rows about fifteen inches from each other. The young shoots are stopped two or three times, and in September they are taken up and planted a little further apart each way. This serves the double purpose of checking the growth and rendering them better able to withstand the effects of a severe winter, and also promotes the formation of a mass of fibrous roots. They are not allowed to flower the following spring, and the young shoots are stopped all over the plants three or four times during the early part of the summer, but no stopping is done after the end of June, as the remaining part of the summer is necessary to ensure the thorough maturation of the young growth. By the middle of September they should be taken up and put in eight-inch pots. Small plants are of no use in the conservatory, for if they are not large enough to produce solid heads of bloom two feet across they are anything but effective. The double yellow and red, known respectively as C. luteus fi.-pl. and C. purpureus fi.-pl., are the only kinds suitable.
Calceolaeia.—Of this well known genus there are two distinct sections, known as the “herbaceous” and the “shrubby.” The first is the most important section, because only fit for pot culture, and when well done presenting a wonderful show of colour with endless variety of beauty. They require peculiar management, and those cultivators will alone succeed who earnestly give their minds to the business. Nevertheless, they are very easy to manage, and those who will follow our directions will surely succeed. It is best to begin with seed, and to sow it, as soon as ripe, in pans filled with light loamy compost, and then place the pans on a moderate hotbed or shut them up in a propagating house, or put them in a close corner of the greenhouse and cover with a bell-glass. They must be kept constantly moist, and as soon as the plants ​are fairly up they must be carefully pricked out into boxes or pans, and when they have grown a little be potted separately in sixties. From first to last, alter they leave the seed pans, they should be grown in turfy loam, with about a fourth of rotten hotbed manure added. There is nothing better for them than loam from the stack, as described in Chapter VI. It should be well chopped up, but should be rather lumpy. Keep them close after potting, but give them air as soon as they have begun to grow again, and as soon as they have filled the 60-size pots with roots shift them into five-inch pots. They must be wintered in a greenhouse, very near the glass, and be very cautiously watered, until the days begin to lengthen rapidly. Beware of the sudden bursts of sunshine that occur in the spring and shade them slightly, or they will suffer, and beware, also, of using any more fire heat than is necessary to protect them from frost.
If the plants are strong shift them into eight-inch pots in February, and be especially careful in watering for a few weeks afterwards. As the flower-stalks make their appearance support them with neat sticks. Plants intended for large specimens for the following year should have their flowers removed immediately the size, shape, and colour of them can be seen, be kept cool all the summer, and shifted into larger pots in autumn, early enough to fill the pots with roots before winter. More care in watering is necessary the second winter than the first. These will probably require tying out before the flowers make their appearance. It must be done with care, for the side shoots easily snap off, and then the shape of the plant is completely spoilt.
When grown from cuttings the treatment is the same as seedlings after the cuttings are rooted. They are easily struck in a cold frame if taken off as soon as they are large enough, and kept close and shady. The cuttings should, of course, be taken from the very best varieties and from plants which have not been allowed to ripen seed. Shade when the plants are in bloom; and, lastly, on the first sign of there being a single green-fly on them give the house or pit a thorough smoking with good tobacco paper. On no account let the green-fly or red-spider get ahead, for they soon ruin the plants, and it is an extremely difficult matter to destroy them; for they shelter themselves underneath the leaves.
The “shrubby” section is chiefly valued for bedding ​purposes, but they also make showy pot plants. Those of them that are of a slightly herbaceous character are to be preferred, and the best mode of procedure is to select in early spring some of the most thrifty from a batch of plants raised from autumn cuttings, and pot them on and keep them in a damp pit very close to the glass. They may be flowered well in 48 size, or they may be grown on, and the flowers suppressed the first season to make great plants of them to flower the second year.
Deutzia.—There are several of this genus in cultivation, but the favorite D. gracilis is the only one worth growing in the greenhouse. As it is quite hardy in the south of England, it needs no heat to keep it in winter. The most ordinary care suffices to ensure an annual display of its elegant white flowers, but if they are wanted early the plant must have a little extra attention. We will suppose you want to secure a good display of deutzias early in the spring. You must begin in the first week of May by planting out a lot of one-year old plants in poor soil, in an open sunny situation, and keep them well watered until the end of June, after which time do not give them a drop. In September take them up and put them in as small pots as their roots can be crammed into without any serious injury, and prune them into shape. It is a very easy matter to prune all the flowers out of them: therefore, by the term “pruning” is to be understood the shortening of any extra long shoots that spoil the contour of the plants. Put them in a cold pit and give them a good watering. In November take them to the greenhouse and keep them cool. In the course of a fortnight put them into the warmest part of the house, and in a week afterwards provide for them, if possible, a snug quarter where the temperature averages 60° to 70°. If this cannot be done, be content with the bloom a little later than a forcing heat would give, and as they are sure to flower without any forcing at all, the most humble appliances are sufficient for rendering perfect justice to the plant.
To raise stock, make cuttings of the young shoots when they are three inches long and growing nicely. Take them off in two-inch lengths and insert in sand, and give them the aid of a steady bottom-heat. A light loamy compost is to be preferred, but the plant will grow in any soil that is neither sour nor pasty. When they acquire some size they may be kept ​several years in the same pots, and if desirable large plants may be divided by cutting through the roots. In such a case it is best to cut them into suitable sizes in September and pot them in very small pots, and winter them in a cool house or pit as dry as possible. In May plant them out in poor soil, and in September following they will be nice plants to pot up for the benefit of the greenhouse.
Heliotrope.—This deliciously odorous flower may be grown by the merest tyro, but it is well to remember that it is the most susceptible to frost of any plant of its class. A geranium or verbena may be frozen several times in the winter, say to the extent of five or six degrees of frost, but such a freezing would kill every heliotrope to the roots. If grown as a pot plant, treat it precisely the same as recommended for the verbena and petunia. It is particularly worthy of observation that it makes a fine wall or trellis plant in a warm conservatory, and, if planted out in a border of light rich soil, will produce flowers all the year round. Even in a cool conservatory it may be planted out to clothe a pillar or trellis, but, of course, it will not flower in winter.
Hydrangea.—For the conservatory and to keep company with the agapanthus in the entrance court, and to fill up amongst groups of pot plants near a summer-house or fountain, the hydrangea is one of the best plants in our gardens. There are several distinct species in cultivation, but the best is our old friend H. hortensis, which produces pink flowers when grown in rich loam, and blue flowers when grown in either peat or loam in which there is a decided trace of the salts of iron. We have employed hydrangeas largely for our plunging system, and have been compelled of course to hit the shortest and surest way of ensuring large heads of flowers with the least possible trouble. In May a number of cuttings are taken from the lower parts of the stems of strong plants. We prefer young shoots with four or five joints, not more than five, and perhaps preferable with only three. The strongest wood may be used, and will be sure to root, but small young cuttings make the best plants. The cuttings have the two lowest leaves removed, and are potted singly in thumb pots in a mixture of leaf-mould and peat, with a very little sand. These are all placed on a moist bottom-heat of not more than 60°, either ​over a propagating tank, or a frame over a dung-bed. They require to be kept moderately moist, and will bear to be closely confined until they form roots. Never having seen a case of damping-off, though we have struck thousands of cuttings, and in various ways, it does not seem needful to warn the cultivator on this head. However, let air be given moderately after the lapse of a week, and thenceforward increase the supply, so that by the time the pots are filled with roots, the plants will be hard and thrifty. When propagated on a large scale they may be dibbled into wet sand, placed over a tank or dung-bed, but we prefer to pot them singly at first, as it is a decided gain in the end. When the thumbpots are full of roots shift to 60-sized pots, using a compost of peat, leaf, and loam from rotted turfs, equal parts of each, keep them in the greenhouse, or warm pit, water frequently overhead, and at the root; give plenty of air, and keep the plants near the glass. When these pots are full of roots, shift into 6-inch pots, the compost to be strong turfy loam, full of fibre; turfy peat, rotten manure and leaf-mould, equal parts, no sand. For the drainage of these pots we use only one large oyster shell, placed over the hole in the pot, hollow side downwards. The plants are shifted into these pots without breaking the balls of earth formed in the 60's, and are at once placed on a bed of coal ashes, or a hard pavement in a shady place out of doors, or plunged to the rim in a bed of cocoa-nut refuse. They have abundance of water, and before the end of October they have attained to an immense size, and have ripened plenty of hard flowering wood for the next season.
The plants are housed at the end of October. A cold pit suffices for their protection, and they have a little water occasionally, and are kept clean as they lose their leaves. In case of severe weather a little care must be taken to prevent them being severely frosted.
From this point the cultivator may proceed either to force a few at a time, or allow them to bloom naturally as the season advances. The first thing to do is to cut them back to about six eyes from the bottom of each well-placed ripe shoot, removing any weak inside shoots that might crowd the head without improving the plant. Next give them a shift to pots seven and a half inches in diameter, with the same soil as the last, and with a mulch of rotten manure an inch thick on the top. Ordinary greenhouse temperature will set them going ​very early in spring, and the blooms will show immediately. Provide some neat green stakes, slender but strong, eighteen inches in length, and tie every shoot, as soon as the bloom is visible, loosely to a stake, as, when the flowers are fully expanded, their weight when wet with a shower will sometimes cause them to fall over and break the stems. All they need after this is abundance of water. They can scarcely have too much at the root, or be too often sprinkled overhead. When the roots begin to run upon the surface, assist them with liquid manure, rather strong, once a week, and by this time the blossoms will be expanding and colouring, and, after acquiring their proper character, will continue in perfection a longer period than those of any other plant in our gardens.
These plants are not to be shifted again till the next spring; then they are to be cut back to about eight buds from the base, and shifted into 10-inch pots, and they will make enormous specimens. The next year they may be shifted to 15-inch pots, and after that it is not advisable to increase their bulk any further. A few cuttings to furnish small useful plants should be put in every year in April or May; or if there is no convenience to strike by bottom-heat, they may be rooted under bell-glasses without heat in June, but it is best to strike them not later than the first week in May to insure the formation of ripe wood for blooming the next year. For ordinary purposes the most useful are yearling plants, which, when they have bloomed once, are to be destroyed. To force them is a mere matter of temperature, and they take a moist heat from Christmas onwards as kindly as any greenhouse plants in the catalogue.
Lantana.—The Lantana is comparatively useless as a greenhouse plant, but we must not pass it by. The stove is its proper house as a pot plant, but the experienced cultivator will turn it to good account, if so minded, without the aid of a stove. In a general way the same cultivation as the verbena requires will suit them, and it is worthy of note that they flower more freely the second year than the first. In any case they like warmth and a humid atmosphere. Well-grown specimens covered with flowers are worthy of a place in any group of ornamental plants, but the odour of the flowers is so unpleasant that they are comparatively useless for making a bouquet.
Libonia.—The beautiful L. floribunda is valued for its winter flowers, which may be likened to those of Cuphea platycentra. It can only be turned to account, however, where there is convenience for keeping it warm in the winter, and those who have only a cool house may as well do without it, for it will simply worry them. It is very easy to propagate and grow. Cuttings of the young wood should be inserted early in the spring, and treated in the same way as the ordinary kinds of soft-wooded plants, the pot being plunged in a nice bottom- heat. The plant being very compact and short-jointed, does not need after it is potted to be frequently stopped; the great thing is to get the lower part of the plant well furnished with branches in its first growth. It is in the earlier stages only that the stopping of shoots is essential. It will thrive in good rich loamy soil, and may stand out of doors with the majority of greenhouse plants during the summer months. In common with many other winter flowering plants the Libonia loses its leaves if kept too cold in October and November. The leaves may not fall at the time, but afterwards, when the plant is in flower, it will be found that many of the leaves are dead. Excess of damp or too low a temperature in winter will very much mar the beauty of this useful plant.
Petunia.—For summer flowers the Petunia is invaluable, as it will flower freely if badly treated, but if skilfully handled may be developed into a sumptuous specimen-plant. The single and double varieties have equal claims on our attention, but the last named are the most popular, the flowers being perfect rosettes, rich and various in colour, and deliciously scented. For hanging-baskets and vases the single varieties are to be preferred, and for exhibition purposes the double varieties are certainly the best, especially when trained to a neat pyramidal outline, dense, dwarf, leafy to the bottom and richly covered with their lovely flowers.
Petunias may be handled in the same way as fuchsias; they must have a generous soil, a kindly temperature during their earlier stages, and at all times the foliage must be kept perfectly clean. To get up a stock of fine specimens place a few old plants in a temperature of 60° in February, and as soon as the young shoots are sufficiently advanced, take them off, and strike in the usual way. If old plants are not at command the cuttings in the store pots may be put in warmth, and when ​they start into growth, the young tops will afford a plentiful supply of cuttings. Put the cutting pots wherever they will have a temperature of 60° or 70°, and as soon as rooted put them into small 60’s, from thence into five-inch pots, and finally into their blooming pots, which may be either six-, eight-, or nine-inch pots; those in eight-inch pots will generally be the most useful for conservatory decoration. When potted into the small 60’s, replace in the propagating frame for a week or ten days, and then remove to a warm frame. Harden off as quickly as possible, and remove to a cold frame, as a continuance in artificial heat will result in general ruin.
Keep them close to the glass, and as soon as the season is sufficiently advanced expose the plants to a free circulation of air, to keep the growth dwarf and stocky. After the middle of May, the lights may be drawn off altogether during the day, whenever the weather is sufficiently favorable, unless the plants are required to be in flower on an early date. The stock intended for affording a late display should, after the end of May, be removed to a bed of ashes at the foot of a north wall, and receive the same attention as if sheltered with glass. It is well to remember that plants growing in pots in the open air require quite as frequent refreshings from the watering-can as others grown indoors. Never let the soil get dry enough to allow the leaves to flag; and, on the other hand, avoid too frequent applications of water. Clear soft water will suffice until the plants have had their last shift, and get pot-bound, then water with weak liquid manure, and continue its use during the whole time they are in the conservatory.
A judicious system of stopping and training must be carried out. Commence by nipping out the growing points of the young plants directly they are established in the small 60’s; and after they are shifted into the five-inch pots, pinch back the side-shoots to within four or five joints of the main stem. After they are stopped, tie them out regularly, and immediately on their recovery from the effects of the final shift, pinch back to the same distance as advised for the last set of shoots. Then no more stopping, but the new growth must be trained in the usual way.
If the system of culture here advised is carried out, and the foliage kept clean by means of a sprinkle overhead once or twice a day according to the weather, there will not be much trouble from insects of any kind; but if green-fly should ​happen to make its appearance, fumigate at once. When they are allowed to get ahead before remedial measures are brought into requisition, it requires double the quantity of tobacco to dislodge the enemies, apart from the injuries they commit. Leave green-fly alone and you may say “we part for ever” to petunias.
Salvia.—The best of the Salvias are stove plants, but there are a few fine species well adapted for greenhouse culture, and of these S. splendens is the best. Treat as advised for Bouvardias, remembering that they love light and warmth, and, therefore, when taken to the conservatory in the autumn must have good places. It is far better to plant them out every year in May and pot them in September than to grow them always in pots. A rich, sandy, loamy soil will suit all the Salvias, and they will also thrive in peat.
Solanum.—The cultivation of the scarlet-berried Solanums is so exceedingly simple that any one with ordinary appliances and ordinary skill may have a grand display of them in the autumn in the conservatory. There are several species and varieties which produce red berries; the one commonly grown hitherto has been S. capsicastrum; but far better, because it makes a bolder bush and bears larger berries, is Williams’s Hybridum compactum. To get up a stock of this proceed as follows:—Place an old plant in a warm house and frequently syringe it. When the young shoots are two inches in length, take them off and dib them into sand in a heat of 60° to 70°. When rooted, pot them in a light sandy compost, and give them a moderate heat until they begin to grow; or sow the seeds in light soil, and place in a steady heat. The latter part of the month of March is the proper time to begin with either seeds or cuttings. From the time they are rooted gradually inure them to ordinary greenhouse temperature and to fresh air, so as by degrees to have them quite hardy by the middle of May. Then plant them out in a piece of rich light soil, in the full sun, fifteen inches apart; give plenty of water all the summer, and slightly train them out, so as to form open heads. They will require to be twice stopped by nipping off the points of all the shoots in the first and last week of June, and after that must grow as they please. About the middle of September take them up very carefully and pot them. In ​this process the roots must be preserved from injury, and as much earth kept about them as possible. When potted, stake them out neatly; shade for a week, and after that keep them in the sunniest part of the greenhouse. If you follow this prescription, their appearance in November will be that of neat shrubs, two feet high and eighteen inches through, completely smothered with bright scarlet berries, full double the size of holly-berries.
Tropæolum.—The showy plants of this family are better known as bedding than as pot plants and it is much to be regretted that they have declined in popularity as subjects adapted for the production of an abundance of gay flowers in the depths of winter. They are easy plants to manage whether in winter or summer, but being very soft in texture will not endure the slightest touch of frost. They all flower fairly in a temperature of 50°.
The most valuable plant of this genus is the old and famous T. tricolorum, a tuberous rooted species, admirably adapted for exhibition and one of the most perfect of ladies' plants, because
to train it nicely is an agreeable task for delicate fingers. To make a fine specimen the tubers should be taken out of the old soil some time during July and be re-potted. The roots are ​delicate, and a light compost should he employed; one consisting of equal parts, fibrous loam, turfy peat, and leaf-mould, and a moderate quantity of silver sand will suit them admirably. The pots must be clean and well drained, and the tubers buried about two inches below the surface. The size of the pot must be regulated by the number of the tubers put in each; one should be put in five-inch, two in six-inch, three in eight-inch, and four in nine-inch pots, and the last mentioned is the largest size that should be employed. The soil must be kept dry until they start into growth, and then sufficient water applied to make the soil just moist, and no more; for very little water will be required until they have made considerable progress. After February, when the trellis is covered with foliage, more liberal supplies must be given, and an occasional dose of weak liquid manure will be of considerable service.
The trellis should be fixed in the pots when the tubers are newly potted, but if there are any reasons for not doing so, they must be fixed in their proper position before the young growth has attained a considerable length; otherwise there is a great danger of its becoming entangled, and probably it will be seriously injured.
The form of the trellis must he left to the taste of each cultivator, and it is of little consequence in which way the growth is trained, provided that it is nicely regulated, and not allowed to run together in an inextricable mass. The subjoined figures will explain themselves. A balloon is, perhaps, the most desirable; and when covered with the cheerful green foliage, and dotted with the scarlet and yellow flowers, the effect is most satisfactory. Flat trellises are very well in their way, and are the most suitable for windows or other positions where ​there would not be room for a balloon. Small feathery sticks, like the tops of pea sticks, about eighteen inches in length, may be employed instead of wire trainers.
The fibrous-rooted garden varieties represented by T. Lobbianum are invaluable for supplying winter flowers. To have them in full bloom throughout the winter, it is necessary that the plants should be well established previous to the end of the autumn, and also that an intermediate house be available for them. Specimens intended for furnishing cut flowers should be trained within about six inches of the glass, to expose the growth to the light as much as possible. Those intended for the conservatory and other purposes, must be trained to trellises or stakes fixed in the pots, and so long as they make new growth they will continue in bloom. Where the temperature of the conservatory is maintained at or about fifty degrees during the winter, a few permanent specimens may be grown in it, and trained up the pillars and rafters, where they will be fully exposed to the light.
The cuttings should be struck in July in the stove or the cucumber house, and potted off as soon as possible after they are rooted. Short-jointed side-shoots should be selected for cuttings. A considerable saving of time will be effected if the cuttings are inserted singly in small pots, as they can then be shifted on without suffering any check. When it is desired to have specimens of extra size for the purpose of obtaining a very large supply of cut flowers, it will be an advantage to commence with plants well established in three or five inch pots, and then remove all the flowers until a few weeks before they are required, so that the energies of the plants shall not be unnecessarily taxed.
Tropæolums do not require so much pot-room in proportion to their size as many other plants, and therefore it is necessary to guard against over-potting them. Specimens trained as pyramids or standards should be put in six- or eight-inch pots, and those intended for training to pillars or rafters in either nine- or ten-inch pots. They bloom more profusely when rather confined at the roots, and exhaustion can be easily prevented by watering them with weak liquid manure.
Veronica.—The shrubby Veronicas are much to be desired for conservatory decoration, for they are easy to grow and keep, and eminently effective. With proper management, they ​flower profusely throughout September, October, and November, and are, therefore, very valuable, for they assist in bridging over the period between the time of the summer flowers going out of bloom until the chrysanthemums are at their best. There are now a considerable number of varieties in cultivation, all more or less good.
When a stock is once obtained, there will be no difficulty in keeping it up, as cuttings of the half-ripened wood will strike freely, if placed in a shady part of the greenhouse, or in the propagating pit. The wood is generally in condition for propagating purposes in May, and cuttings struck at that period will make nice little plants, and produce a few spikes of bloom in the autumn; but, with good management, they will become large specimens, not less than two feet through by the autumn following. Instead of keeping them in pots all the year round, which entails an immense amount of labour during the summer season in keeping them properly supplied with water, plant them out in the second and subsequent seasons in the open border, and they will almost take care of themselves. The way to proceed is to cut them back early in March, and to let them make new growth near the glass, to insure its being firm and strong-jointed, and then by the end of May turn them out of the pots, loosen a few of the roots round the outside, and put them out in the border. The soil should be light and rich, to insure a vigorous growth, and, at the same time, promote the formation of an abundance of fibrous roots. The distance at which they are put apart must be determined by their size. Small plants, with but one or two leading branches, may be stopped twice, but large specimens should not be stopped more than once, and in either case none of the shoots must be pinched back after the first week in July. Early in September take them up carefully, with as much soil as possible adhering to the roots, and put them into the smallest sized pots practicable. Bushy specimens, from eighteen to thirty inches in diameter, will be the most suitable size for the conservatory, but if they are required larger, they can be easily produced by planting them out annually.
Verbena.—The directions given for the cultivation of the petunia might be referred to for the saving of space under this head, but we could not hope to satisfy the reader by disposing of the Verbena in so curt a manner. Verbenas are ​pretty when grown in pots under glass, but for conservatory decoration are less useful than petunias.
For the purpose of laying a good foundation, in the month of March, take the tops off the healthiest autumn-struck plants, and strike them in a good bottom-heat. They will begin to grow freely as soon as furnished with roots, and this will be the best indication the cultivator could have of their being ready for potting off. Prepare a compost by mixing together two parts of turfy loam and a part each of leaf-mould and old hotbed manure, and about a sixth part of sand. Put the compost in the house a day or two before required for use, and then put them singly in three-inch pots. They should remain a few days in the propagating pit after they are potted off, and then be removed to an intermediate house, where they can be kept rather close until the roots become established in the new soil. They must not be coddled, but it would check the growth too much to take them to the greenhouse, where they would be fully exposed to a free circulation of air. If there is no choice about taking them direct to the greenhouse, then place them in the warmest corner, and keep the ventilators near them closed for a few days.
When they are established in the small pots nip out the growing points, to cause them to produce side-shoots, and when the latter are about two inches in length, stop them by nipping out the points. They will probably require to be shifted into larger pots before they are stopped a second time, but very often it is better not to repot until afterwards. It is a golden rule to shift when the pots are well filled with roots, but before they become potbound. Specimens in six-inch pots will be quite large enough for ordinary decorative purposes; but if they are required extra large shift them into eight- or nine-inch pots as soon as they are well established.
Training must be proceeded with after the second stopping, and the simplest form possible should be adopted. All balloon or other wire trellises should be avoided, and a few neat stakes only be employed. From the time they are established in the small pots until they begin to bloom, a cold frame or greenhouse, where they can be placed near the glass, and enjoy a fresh circulation of air, will be the best position. Water liberally, and after the pots in which they are to bloom are well filled with roots, use rather weak liquid manure alternately with soft, pure water. Syringe them overhead ​occasionally, and keep a sharp look-out for green-fly, which, if the plants are allowed to suffer from the want of water, or kept in a close stifling atmosphere, will soon become troublesome. Tobacco smoke is one of the very best remedies, but some degree of caution is necessary, because the tender foliage is very susceptible of injury.
Viola.—The greenhouse culture of Violets is extremely simple, but it is just as easy to fail as to succeed. The best TREE VIOLET. mode of obtaining a supply of such hardy kinds as the Russian and Neapolitan is to lift the plants in October, and plant them in turf pits or in frames on a gentle hotbed of leaves. The lights should not be put on until there is apprehension of frost, and they must be kept regularly watered and have air at all favorable opportunities. A plantation for the purpose should be made every year, in April, by putting out young rooted runners in beds of rich sandy loam, with which plenty of charrings from the smother heap have been mixed. The greenhouse species, such as V. arborea (the Tree Violet), and V. hederacea (the Ivy-leaved Violet), should be grown in rich sandy soil, and, after flowering, should be put out of doors, in a shady place, until the end of September. The double varieties of the Russian, such as The Czar, The Queen, and others, make beautiful pot-plants for the conservatory if planted out in April and potted up in September, in the same way that bedding plants are treated.