Some roses, like Rosa rugosa and its hybrids may be shaped to some extent by gentle clipping in winter to make dense hedges while maintain the natural outline of the shrub. Some Hybrid Musk roses will grow into a thick, thorny screen up to 2 m in height covered in fragrant flowers all summer long, if their unpredictable growth is curbed by training them on horizontal wires or chain-link fencing. If you grow a rose hedge to line a path then use the upright cultivars instead of those with unpredictable growth as these may impede the pathway.
In a small garden use Floribunda roses to form a tall hedge as these are generally upright plants with little spread. Plant them in two staggered rows to form rapidly a screen of about 1.2 m tall. If you are using some shorter-growing old garden roses to form a hedge of similar height keep an eye on them as they are more vulnerable to mildew because of close planting. Even the old roses may have attractive foliage they will only flower for a shorter period of time in midsummer.
You can use roses to divide one part of garden from another or to hide some unpleasant shed. Train climbing roses or ramblers on decorative screens of desired height, formed by constructing open, wooden frameworks. This way you will have a delightful separation for your garden or a pretty screen to hide your shed or even the compost heap. If you are going to buy a ready-made wooden or plastic trellis that is available on the market, make sure you buy a sturdy one since it has to support a considerable weight and to last for many years.