IT is questionable if any glass structure in a garden can command such general admiration as a Rose-house, or if there is one where so much beauty and fragrance are to be found. Where choice flowers are in demand through the winter and spring months, no collection, however beautiful, appears complete without Rose-buds. Perhaps no plant-house can give so much satisfaction or afford so much pleasure generally, and none is so remunerative for the labour expended, as a Rose-house. Yet in private establishments it is seldom we find a house exclusively set apart for Roses. Houses are frequently occupied with far more unworthy subjects; and Roses in the majority of cases are largely required where quantities of cut-flowers are in demand. They have, however, to be produced in many gardens under great difficulties, causing much more labour, to say nothing of the uncertain results that may follow, than would be occasioned by devoting a house entirely to their cultivation. Where large supplies of Roses are required - either Teas or Hybrid Perpetuals, or both - say from Christmas onwards, the Rose-house is indispensable to meet the demand with any degree of certainty.

The kind of house best adapted for Roses is undoubtedly a span-roofed structure running north and south. The size entirely depends upon circumstances; but in a house 30 to 40 feet long, 20 feet wide, and 15 feet high, an abundance of Roses can be produced. A walk 3 feet wide should go all round, side stages 3 feet wide on either side and ends, and a bed in the middle 8 feet wide. The height the bed should be raised above the walks entirely depends upon different tastes. It should not be lower than the side stages, or else the Roses at the bottom will not obtain sufficient light, when the side stages are filled with plants in pots, to be very satisfactory : 2 feet 6 inches is a height which leaves ample room for drainage and border above the level of the walks. Preparation should be made for a border under the side stages in which Roses can be planted to train up the roof under each rafter. It is not advisable to allow those planted to cover the entire roof, or else light will be too much excluded.

It is essential that the borders should have a drain to carry away the water that would otherwise stagnate about the roots, and in time prove fatal to the wellbeing of the Roses. A quantity of broken bricks should be placed in bottom for drainage about 1 foot in depth : this will leave a space of 18 inches for soil, which is ample. The side borders can be made more shallow if the growth is kept in due bounds, as suggested. A turf grassy side downward should be placed over the drainage before the compost is put in. The compost most suitable is rich fibry loam, of rather a tenacious nature : a quantity of fine bones, charcoal, or wood-ashes is also beneficial, and coarse river-sand. It may be as well to say here that vegetable matter incorporated with the soil for the border is not advisable : it decomposes too quickly, and has a tendency to sour the border. When necessary, feeding is best done by the application of manure-water and rich top-dressings. An arched trellis should be provided for the centre bed, to train the Roses to, as they show themselves off to greater advantage thus than any other way I am acquainted with.

It is necessary to consider the preparation of the plants for planting. They can be readily raised at home, as the majority of Teas do well on the Manetti, upon which stock they can be grafted with ease. Stocks can be purchased cheaply, and potted in small pots; and when root-action is well commenced, and the wood intended for the scion is half-ripened, the operation can be performed with success. They can also be propagated by cuttings from half-ripened wood, which undoubtedly is the best. They are preferable on their own roots : if on the Manetti, they should be potted or planted below where worked, so as to get them upon their own roots. Plants ready worked and growing freely can during April be purchased from any well-known nurserymen where Roses are largely grown. When obtained while growing, they frequently are considerably checked in transit, and stand still for a long time. Therefore, if possible, home-prepared plants are preferable. If rooted in early spring from half-ripened wood, it is surprising, when afterwards planted out, what progress is made in a season.

We will consider the plants in 5-inch pots, which should be the first shift after the scions are united to the stocks, or after the small pots are full of roots in which they would be potted after being rooted. If a slight bottom-heat can be given for a time, growth will be rapid, and flower-buds as they appear must be removed. When the young plants become thoroughly established in their pots, they are in a good condition for turning out for planting, provided the borders in the house are ready, and the soil is well warmed. If the borders are not ready for planting, the plants should not be allowed to stay in the 5-inch pots to become checked, but should be transferred into a larger size. Bottom-heat is still serviceable, but the plants before planting-time should be removed from the bottom-heat. Those intended for the roof should be kept in pots until they have attained a sufficient size to reach from the border well through the stage : abundance of air should be given to the plants when favourable, to obtain a sturdy, compact growth.

Airing, watering, syringing, temperature, etc, should be conducted as recommended in previous numbers of the ' Gardener' on Roses. Those intended to be planted out should be attended to with as little delay as possible, as under the planting-out system they attain greater strength and vigour, and cover much more of the trellis than if kept in pots through a good portion of the season. As the external air becomes warmer, artificial aid can be dispensed with. While growing rapidly, the house can be closed early in the afternoon, so as to allow the temperature to rise considerably by sun-heat.

When autumn approaches, the wood must be thoroughly hardened and ripened, and the plants brought to a complete standstill by keeping the house much drier and cooler. Ripened wood and a good season of rest are essential to the successful cultivation of Tea Roses when planted out under glass. The latter to a large extent has to be forced upon them, as they are rather perpetual in their nature, and continue to bloom and grow in autumn if means are not taken to prevent them. I have seen failure result from this constant-growing system. They continue to nourish tolerably well for a time, until their vital energy is exhausted. They then force rest upon cultivators, and when wanted to grow, decline, and if pushed against their will, soon dwindle and die. This will not be the case if a natural system of cultivation is pursued. The forcing of rest upon them need not be severe, but sufficient to bring them to a standstill, and nothing accomplishes this better than a low temperature. This is quite easy for a season or two after planting; but when rest is required much earlier in the season, to be ready for starting to produce Roses in winter, the resting period is not so easily accomplished by a low temperature.

An early growth, dryness both in the atmosphere and at the roots, with abundance of air, are the only means that can be employed.

The young plants subject to winter maturation, after rest should be slightly pruned by removing weak and unripened shoots, and should be again slowly started into growth. It will be wise if all flowers are sacrificed the first season, and the strength of the plants devoted to the production of wood. The second season the growth should be rapid and strong, and should be ripened as early as possible, so as to again start them earlier into growth, in order that the plants may be trained to make their growth earlier each year, until they can be rested, and be ready for starting towards the middle or end of October. Two rows of 4-inch pipes all round the house will be ample for maintaining the desired temperature. The side stages may be occupied with Teas or Hybrid Perpetuals in pots, which can be introduced in successional batches from Peach-houses or vineries, or any place where they have been started. These side stages are also valuable for growing a number of young Teas in 5- and 6-inch pots - "propagated every season" - for a few autumn flowers; or plants of Gloire de Dijon, Marechal Niel, Reve d'Or, and others of a similar growth, thinly trained under the roof - after the Hybrids are over, and Roses in abundance can be obtained from outside - to be eventually, when ripe, trained round four or five stakes, or any other form.

A strong shoot should be selected, and one only grown, and allowed to extend without stopping. The two first varieties will often make shoots 20 feet long in a season. For some time I propagated in the spring for this purpose, but found they did not ripen sufficiently to produce real early flowers. The month of June is now preferred, and the young plants are nice stuff in 5-inch pots (on their own roots) before winter, which, if kept cool in a late Peach-house for a time, and then started, will ripen their wood early, and produce as many as twenty-six flowers from the shoot by the end of January, every bud along the shoot producing a flower. When sufficiently ripe towards autumn, they are placed outside for a time to further harden them. They should be made secure in some sunny position where the wind will not break them.

Such varieties as Gloire de Dijon, Lamarque, Reve d'Or, Belle Lyonnaise, Cheshunt Hybrid, Marechal Niel, Celine Forestier, are most suitable for training up the roof. The first mentioned is the best for early forcing. For early forcing to bloom during winter, the following free-growing, profuse-flowering varieties will be found invaluable : Saf-rano, Isabella Sprunt, Niphetos, Duc de Magenta, and Rubens (a fine old Rose). The following bloom well in the same house a little later : Alba rosea, Adrienne Christophle, Goubault - very free in spring - Mad. Falcot, Devoniensis, Homere, Jules Margottin, Louise de Savoie, Mar-celin Roda, Marie Van Houtte, and Catherine Mermet. Many varieties of Teas, when subject to early work, soon die out; others are shy; while others refuse to grow until the season is far advanced, - for instance, Aline Sisley, Anna Ollivier, Bougere, Perle des Jardins, Perle de Lyon, and many others, do not appear to do well if subjected to much unnatural forcing : they should be grown in pots, and allowed to come on more naturally.

The first mentioned for the Rose-house bed are unsurpassed, where delicate and fragrant buds are esteemed.

Wm. Bardney.