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they quite fill the pot. So long as the roots are thus making and filling the pot, the leaves and woody parts of the plant will increase, and there will be no indication of flowering till the roots have occupied all the space allotted to them.

With the compost just described, there will be no need of manure-water for awhile, but when the flower-buds begin to form there will be too little nutriment in the earth to supply the new and increased demands of the plant, and to secure a satisfactory bloom, we must add occasionally a little guano or liquid manure to the water. The best way to prepare a liquid manure, is to set upon a shelf in some convenient place an old vinegar or other barrel that is tight, provided with a faucet. The shelf must be high enough to allow a watering pot or pail to stand under the faucet. In the bottom of this barrel, and just above the faucet, make a staging of two sets of parallel strips of wood, crossed at right angles, upon which the manure may rest, and through which the water may run as it percolates the manure.

In the cut, the dotted lines on the barrel show the situation of the staging, which is also shown by itself. This staging will prevent the manure from passing into the faucet and choking it. Fill the barrel thus prepared nearly full of stable-dung, and tread it down well. Pour in water slowly till the barrel is full; let it stand for two or three days before you begin to draw off. At first this water must be diluted to be safely used, one part manure-water to at least three of pure water, but as the plant becomes accustomed to it, stronger doses may be given. Such a barrel of manure will bear several saturations with water before all its strength is drawn out.

If guano is used, put one-quarter of a pound to two gallons of water; let it stand twenty-four hours, then use like the water from the barrel. If the guano-water is prepared in a barrel, the staging must be covered with a fine wire or a cloth-strainer, to retain the

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finer particles. This proportion of guano to water is advised on the supposition that the guano is of the best quality. Such guano is, however, scarcely to be obtained, and consequently the best way is to make what seems a solution of moderate strength, and then be guided by experience as to weakening or strengthening it.

This application of liquid manure is to be continued only while the buds are forming, as it will, if used after they begin to expand, often stimulate the plant enough to turn them into leaves. This is particularly the case with hard wooded plants like Daphnes, Camelias, etc., to which liquid manure should be applied only during the dormant or growing, not the blossoming, season. It seldom happens to Roses or Pelargoniums, as they are gross feeders.

Surprising as are the effects of liquid manure, they are no more than should be expected, for the food of plants must be diluted before it can be absorbed by the spongioles of the roots, and such dilution is the only chemical or mechanical means to which nature resorts for the development of the crops, flowers, etc., in the fields. The power which guano in solution exerts, is greater than that of any other manure, and indeed in its dry state it is likely to injure rather than benefit vegetation. In the greenhouse, whether applied as we have directed, or put on the surface in powder, no injury need be apprehended, as the daily watering will in the latter case soon carry it below the surface; but when used on a large scale in agriculture, whether as a top-dressing or ploughed in, its good effect depends entirely on the amount of rain that falls during the season.

STOCK PLANTS.-As yet we have made no mention of other classes of plants which are to be attended to in August.

First, Stock pot plants. These will generally be Camelias, Daphnes, Cape Jessamines, Laurestinus, Lemon Verbenas, and other hard wooded plants which grow too rankly when planted in the ground, or which if planted out would be liable to injury from sun, wind, and transplantation. The way to treat such plants in the late spring or early summer will of course be described when we arrive at the proper time. What we have now to do is to take them as we find them. Such of them as have outgrown their pots

and can be repotted, should, before they start afresh to grow, be removed into pots or tubs a size or two larger than the old. Make the drainage as before described; then examine the ball which you have taken out of the old pot, and if there are any signs of worms, hunt them out and kill them; remove all dead roots, score the sides of the ball a little, if it is much matted together, so that in healing the old wounds the plant will naturally throw out new fibrous roots from the calluses; remove the old earth from the top of the ball till you come to the roots. Now set it on the earth which covers the drainage in the new pot, and fill in between the ball and the sides of the pot with the fresh compost, and work this in well with a stick; then shake together; finally add fresh earth to the top of the bared roots till the pot is full. Water and treat as in other cases, although it will not be necessary to defer putting these plants at once into their final places in the greenhouse. Water Camelias abundantly as they start to grow. Give Azaleas less water and more sun. House Euphorbias. An excellent pot for such plants will be shown by and by.

Another class of plants includes those, which, owing to size or other peculiarities, cannot be repotted. In dealing with these, remove the upper earth in the pot down to the roots, and replace it with compost. They will need manure-water oftener than the others.

Pinch back roses in pots, make cuttings of Verbenas etc., to blossom late in the spring; as the Fuchsias, etc., lose leaves give little water and keep in the shade till spring.

CONSTRUCTION.

The greenhouse on our estate, as shown by the plan, is a spanroofed house with straight sashes. The use to which any glassroofed structure is to be put should decide its character. A building for the growth of grapes or fruit, where only one side is to be exposed to the light, may with some propriety be a lean-to house (i.e., one of its sides may be a perpendicular, dark wall); but where plants which should be equally well grown on all sides are to be cultivated, the light should be admitted from as many points as possible. A distinguished English writer says: "Of all forms for

a geeenhouse, that of a lean-to is decidedly the worst, and that of a span or curvilinear the best." When trained upon walls or trellises peaches and vines may be grown to the greatest advantage in lean-to houses, but greenhouse plants seldom can, as the merits of the latter greatly depend upon symmetry of form, and this cannot be attained unless every part of the plant be equally exposed to light, air, and sunshine.

"It seems now almost universally admitted that the span or curvilinear form of roof is best adapted for this purpose; and the ends of the house should front north and south, although under peculiar circumstances they may be usefully constructed to face the east and west; the more so if they are glass on all sides to within a foot or so of the ground.".

It will be seen that this author uses the terms span and curvilinear as alike distinct from "lean-to," although they are far from being so. A span-roof, as we have shown, is ordinarily shaped with the sashes and the lines of the roof straight. But the lines of roof and sash in a spanroof may be curvilinear, and there may be the same differences in the lines of a lean-to roof, there being no more re

striction to straight lines in this than in a span-roof.

To appreciate the respective advantages of these different forms, we must consider why glass is used for a roof. However much artificial heat fire will give, we must, to grow perfect plants, depend on the sun for light and heat; yet the position of the sun in the heavens differs greatly in different months. Out-of-door plants, in the growing season, have the sun's rays nearly vertical for a part of the day, and the vertical rays are the hottest. In greenhouses the order of the seasons is reversed, and the growing season is at the time when the sun's altitude is low, and his rays relative to the earth's surface never approximate to the vertical direction. Our aim must therefore be to arrange our glass roof so that the rays shall strike it nearly at a right angle. With a rectilinear roof, whether "span" or "lean-to,”· some constant angle is selected; such, perhaps, as will secure the perpendicularity dur

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ing the coldest months, and as the sun increases his altitude, this angle will become more or less desirable, and we must then depend upon the increase in the hours of sunshine, so that a decrease in quality may be made up by increase in quantity; or we can increase artificial heat. But with a curvilinear roof, this difficulty is lessened, as some part of its changing form will always be nearly perpendicular to the line of incidence of the rays. There is, however, an objection to curved roofs. expensive to build, because of the difficulty with bent to curves without injuring its strength. therefore generally made of metal, which can be cast of any strength and shape required. This change increases the expense as well as the liability to damage from expansion and contraction in a climate of such extremes as ours.

They are more which wood is Curved roofs are

Still, when a greenhouse is to be built by a person with money enough to allow of his considering the best of its kind to be an essential feature in economy, a curvilinear span-roof is beyond question the best for all plants which Nature intends to be symmetrical. Both these styles of houses may be rendered more effective still by the application of the ridge and furrow sash, which is described in another place.

This distinction between plants which branch in many directions and fruit trees and vines, whether grape or flowering, must be kept constantly in mind while discussing glass structures, as neglect of the peculiar wants of the different plants the gardener may wish to cultivate, has been the cause of the almost complete uselessness of many very elaborate and expensive glass houses.

A greenhouse is a building in which plants may be stored for the winter, and in which a moderate growth may be promoted; we may, if we please, divide the house so that some portions can be heated hotter than others, and the plants in it forced more rapidly for exhibition in the conservatory, when in bloom; but as a whole building it should be a cold rather than a hot house.

Some portions of the floors of greenhouses-around the supporting posts, and at the back walls and ends, may be filled in with loam, in which to plant vines of different species, Roses,. Passion

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