Rose species are propagated by seeds which are either sown as soon as the hips are ripe or are stratified in sand until spring. If allowed to become dry they may require two years to germinate, but if treated as above they generally sprout the first spring. Many species may be propagated by means of cuttings of nearly ma ture wood taken during summer and rooted under glass. Others will grow mature wood cuttings taken in autumn and rooted in the spring like currants and gooseberries. Lay ering is generally practised with such species as do not root readily from cuttings; for example, R. hemisphterica and R. eglantersa. Some species such as the cinnamon rose (R. cinnamomea), the Carolina rose (R. carolina) and the Damask rose (R. damascena), may be propagated by suckers, division or by cuttings of the roots which in the last case should be dug in autumn, stored in sand or sphagnum in a frost-proof cellar until spring when they are planted in nursery rows. Grafting and budding are also practised, but are frequently unsatisfactory where regular intelligent attention cannot be given to the removal of the suckers that gen erally spring from the stock. For greenhouses and for forcing, cuttings of semi-mature wood are nearly universally used. They may be taken at any time, rooted with bottom heat in sand, in pots until large enough to be trans plant upon the branches.
In general, roses thrive best upon loamy soils, rich in plant food and humus, well drained but moist, in situations sheltered from the wind but where they will receive the sunlight at least half the day. They do not generally succeed upon very loose or sandy soils, but often do upon heavy clays. They are seldom difficult to transplant with ordinary care, are easy to cold vats and generally• simple' to prune. The' re moval of weak and old wood is the most im portant pruning detail. But care must be taken especially with climbing varieties to preserve the long sturdy shoots, since they are most prolific of blossoms. Indoor roses cultivated for cut flowers are generally pruned so as to have the flowers borne singly at the ends of long stems sometimes, as in the case of American Beauty, exceeding four feet in length. But this is a special florist's practice and is depend ent not only upon the method of pruning but upon the management of the plants otherwise. In the garden the plants may usually be set about 30 inches apart in beds about four feet wide, the plants of one row being preferably opposite the intervals of the other so as to obtain full light and air. Beds of this width need not be tramped on when the flowers are being gathered.
Cultivation consists in keeping the surface loose and open at all times by raking, a rather shal low forking being given each spring. In the autumn a liberal mulch of stable manure should he spread upon the beds and the coarser parts removed in the spring before the annual fork ing. The removal of all dead, failing or puny shoots should precede the cultural operations. Many gardeners give applications of liquid ma nure just as the flower buds appear and pref erably preceding a shower. When well man aged a rose bed should be satisfactory for 10 or more years.
A large number of insects feed upon the rose both out of doors and in the greenhouse. Of those which sometimes prove troublesome in the garden the rose beetle or chafer is perhaps the most annoying, since it feeds upon the petals of the opening flowers, thus ruining them. The only remedy which has been satisfactorily applied is hand picking. Plant lice (see APHIS) and scale insects (q.v.) are often found upon roses, but in the garden are not usually very troublesome. Slugs occasionally skeletonize the leaves by working upon the undersides, and several caterpillars, beetles, etc., also live upon the foliage, usually, however, in insufficient num bers to do damage. In the greenhouse some of the above species may appear, but they are usually debarred by correct methods of manage ment, especially as to ventilation, temperature and humidity. The red spider, not an insect but a mite, is sometimes troublesome where the air is allowed to become too dry. Management will also prevent the so-called plant diseases occasionally found in poorly ventilated houses ; indeed, attention to the details mentioned is in many leading houses found more expedient and satisfactory than recourse to the so-called reme dies for either insects or maladies.
Bibliography.— Buist, 'The Rose Manual' (Philadelphia 1844, etc.) ; Prince, 'Manual of Roses' (New York 1846) ; Parkman, 'Book of Roses' (Boston 1866) ; Shaw, 'The Rose' (Saint Louis 1882) • Ellwanger, 'The Rose' (New York 1882; 2d ed. 1892, New York) ; Hatton, 'Secrets of Rose Culture' (Huntington, N. Y., 1891) ; Hole, 'A Book About Roses' (1894) ; Bailey, L. H., 'Cyclopedia of American Horti culture' (1904) ; Mellias, 'Book of the Rose' (1905) ; Pemberton, J. H., 'Roses : Their History, Development and Cultivation' (1908) ; Thomas, H. H., 'The Rose Book' (New York 1914) ; Thomas, C. C., Jr., 'Practical Book of Outdoor Rosegrowing' (Philadelphia 1914) ; Sanders, T. W., and Their Cultivation) (London 1914); Joret, C., 'La Rose) (Paris 1892).
M. G. Kane% • Crop Expert.