I have at some length given the directions for building, and the same will apply precisely to houses that are built to grow roses and carnations, except the shape, size and aspect. The object sought in these houses is to get every possible ray of sunshine, and besides direct sunshine, light; for there are many days, yes, and weeks, in the dead of winter in our northern clime when we don't see the sun at all.
There are three styles of these houses and all have their champions. They are the long-span-to-the-south, the equal-span, or nearly equal-span, and the short-span-to-the-south. Twenty years ago and less the long-span-to-the-south house was considered by many as the only house for winter roses. Then came the very reverse of that, the short-span-to-the-south, and within seven or eight years many good growers have gone back to the simple even-span house, and from results believe that it is as good a house as any.
All of these styles when built for flower producing face to the south, or what is still better, facing a few points to the east of that. The ridge is running east and west, or a few points north of east, and south of west. It is obvious that only one style of these three can have a range of glass attached, and that is, of course, the short-span-to-the-south. If attached, the equal span would shade the house to the north of it, making one-fourth at least of the north house useless, and the long-span-to-the-south connected would be still worse and out of the question.
So excepting the short-span-to-thesouth the other two styles are always built with their walls some eighteen to twenty feet removed from another structure. Where land is cheap, and most large establishments are so situated, this is no great consideration; and if it takes more heat, that also is not an objection, as the results are sufficiently better. The long-span-to-the-south doubtless predominates throughout the country, but that does not confirm it as the best, because florists, like all other classes, are great copyists, and if one or two leaders said so the rest would follow like sheep, notwithstanding the fact that millions of fine roses have been produced for years in the long-span-to-the-south houses.
I see nothing about them in any respect to warrant their being called the best houses for the purpose. If there is any merit, and there undoubtedly is, in the short-span-to-the-south, then the others must be entirely wrong. They are expensive to build, awkward and costly to arrange the benching in, more laborious to attend to, and do not get the direct rays of the sun to the same extent as do the equal-span or short-span-to-the-south.
The front wall is usually four feet six inches (and eighteen inches or two feet of it glass), the back wall eight feet, the back or short rafter eight feet and the long south rafter sixteen feet. These are the dimensions for a house nineteen feet wide; if twenty-two feet wide the long rafter is eighteen feet and the short one nine feet. An upright 1 1/4-inch pipe supports them under the ridge, with a branch holding a 1-inch purlin a foot below the ventilator headers, and another upright supporting another 1-inch purlin is needed half-way between the plate and ventilator purlin. The ventilators of these houses are always on the south side of the ridge and open at the ridge; and as the ventilation. should be afforded to the fullest extent, it should be continuous and deep.
It is thought necessary to raise the benches so that the plants will be at about an equal distance from the glass, and the benches are arranged in a 19-foot house as follows: The south bench three feet and path eighteen inches or two feet; the middle bench six feet and the back or north bench three feet. If the house is twenty-two feet the front bench is three feet and the back bench three feet and two middle benches five feet each, with three paths, each path and bench being raised a foot or so till the back or north path is four feet from the ground. If heated with hot water the pipes are mostly under the benches. If steam is used the flow is most likely on the side walls and the returns beneath the benches. It is as well to add, because it is the truth, that these houses, while getting the sun's rays in winter very obliquely, get it broadside in the summer, making them terribly hot houses in the summer months.
The short-slope-to-the-south is also built sometimes nineteen feet wide and sometimes twenty-two feet. The walls are of equal height, usually five feet. There is a path against the north and south walls and one dividing the two benches, which are about six feet six inches each. The paths being removed from the walls gives you the ideal place to hang your pipes, whether steam or hot water.
An improvement over the house just described, and one that is giving the owner the greatest satisfaction (after a trial of several of them he has added some more of the dimensions of 22x400 feet), is twenty-two feet from outside to outside of posts. The south or short bar is nine feet, the long or north bar is eighteen feet, and the walls five feet high. On the south side there is a path next the wall, then a 6-foot bench, then a path, another 6-foot bench, another path, and against the north wall a 3-foot bench. There is a l1/4-inch pipe under the ridge with a branch from that supporting a purlin near ventilator headers, and another row of 1 1/4-inch pipe supporting a purlin three feet lower down the roof on the north side.