First let me state at once that the majority of roses grown in gardens are hybrids, that is to say they are the result of intermarriages arranged by the growers, between various rose species. In many cases the growers themselves are uncertain of the exact parentage of some of the roses, so it would seem quite unnecessary for the amateur gardener to worry unduly about this matter.
What the gardener does want to know is the general habits of growth of the roses in his care. This he could find out by observation, but he can also find it out by the name and classification of the plants he buys. I am going to explain the main classification in a somewhat unorthodox way.
First there is a division into two groups. In one, the rose plant grows like many other shrubs, by adding more new stems to the old wood each season. In the other the new season’s growth comes mainly from below the soil level, or from just above it, and this gradually supersedes the old wood. In this second class there are plenty of roses that send out some new growth from the upper parts of the old stems, but their chief annual growth comes from the soil level.
Look at the garden roses, and you will easily be able to distinguish the two groups. All the roses growing as dwarf bushes in the rose beds, the standard tea roses, and some of the climbing roses have the habit of sending out new growths from the old wood. The rambler roses, such as Dorothy Perkins, send up fresh long stems from the soil level each year. These rambler roses are therefore a class apart when it comes to pruning They are the wichuraiana roses.
Now look at the others; some of them make bushy rounded growth, but occasionally we find varieties that tend to climb. There is a bush, Mrs. Herbert Stevens, for instance, but there is also a climbing variety. Apart from the fact that the long climbing framework of old wood is retained when the rose is trained on a wall or pillar, there is not much difference between the methods of pruning the two. Both are cut back enough to develop fresh growths.
The beginner need not worry much concerning the differences between the bush roses. Some have the habit of one rose species, and some the habit of another, but in view of the mixed blood in most of them, the differences are not always very marked. It is sufficient for ordinary purposes to recognize the difference between a bush rose and a standard rose, and this is simple enough. The standard has a single main stem, with a bush at the top, i.e., the bush is elevated to a point nearer the eye level.
Occasionally the rambler type of rose is grafted on to a standard, and is sold as an umbrella standard.” This merely signifies that the rambler will grow its new stems from the head, instead of from the soil level.
Now for the use of roses in the small garden. Ramblers are useful to cover all sorts of screens, or sometimes to hang over banks. Climbing roses, which, because they keep growing from the old wood, sometimes run up to 20 or 30 ft. on a house wall, are obviously better plants for walls and other permanent sites. The climbing Mrs. Herbert Stevens type does well on pergolas, too, or in any position where the rose can extend to an almost unlimited extent.
Standard roses are useful in all sorts of odd places; in enclosed small gardens, alongside front garden walks, as dot plants in odd places in the garden design, here and there in the ordinary flower-beds or borders, or in groups in parts of the large rose garden.
Bush roses make a brave display in small rose beds—small for preference because if there are too many roses in a bed, pruning and attending to them becomes difficult. If space permits, the grouping of roses of a single colour in each bed is recommended, and formal rose gardens are delightful if the colours are graded and the cultivation is of a high standard.
Planting roses is exactly similar to the planting of any tree or shrub. Deep soil cultivation is necessary, and sufficient humus should be present in the soil to hold moisture in dry weather. There is a popular belief that roses like clay. They do prefer a heavy loam, usually, but certainly will not thrive in unworked clay. Bone-meal used in preparing the beds is a great help, and nitrate of potash and superphosphate of lime are both useful fertilizers (apply separately, the superphosphate in spring, and nitrate of potash during growth). Lime in the soil is also an essential of success in rose culture.