An open situation, not shaded but sheltered from strong winds, is what the rose prefers. October and November are the best months for planting roses, but if the weather be wet or frosty and the soil sticky, the plants should be placed in a sheltered place and protected by green boughs or matting until suitable conditions prevail. The planting should never be deep, the upper most layer of roots being about 2 or 3 in. below the general level of the surface, and the soil should always be kept stirred with the hoe during the summer months. In regard to pruning, roses vary considerably, some requiring close cutting and others only thinning out; some again, such as strong growing climbers, may be safely pruned in autumn, and others are better left till spring. Instructions on this point as to the several groups of varieties will be found in most rose catalogues. It may be laid down as a general rule that the more strongly growing varieties should be less severely cut back than the weakly varieties; and, again, the more tender the variety, the later in the spring should the pruning be done, April being the best month for pruning teas and noisettes.
Where dwarf beds of roses are required, a good plan is to peg down to within about 6 in. from the ground the strong one-year old shoots from the root. In due time blooming shoots break out from nearly every eye, and masses of flowers are secured, while strong young shoots are thrown up from the centre, the plant being on its own roots. Before winter sets in, the old shoots which have thus flowered and exhausted themselves are cut away, and three or four or more of the strongest and best ripened young shoots are reserved for pegging down the following season, which should be done about February. In the meantime, after the pruning has been effected, plenty of good manure should have been dug in lightly about the roots. Thus treated, the plants never fail to produce plenty of strong wood for pegging down each succeeding season.
One of the most troublesome fungoid pests of the rose is the mildew (Sphaerotheca pannosa). The young shoots, leaves and flower-buds frequently become covered with a delicate white mycelium, which by means of the suckers it sends into the underlying cells robs its host of considerable amounts of food, and causes the leaves to curl and fall early. The spores are pro duced in great abundance and carried by animals and the wind to other plants, and so the disease is rapidly spread. Later the
mycelium increases and forms a thick velvety coating on the young shoots, and in this the winter stage of the fungus is produced. Spraying with potassium sulphide (I oz. to 2 to 3 gal. of water) is a good means of checking the spread of the disease.
The rose rust (Phragmidium subcorticaturn) appears on both cultivated and wild roses in the spring, bursting through the bark in the form of copious masses of orange powder consisting of the spores of the fungus. These spores infect the leaves, and pro duce on them in the summer small dots of an orange colour and, later, groups of spores that are able to live through the winter. The last, the teleutospores, are of a dark colour, and it is by these that the disease is started in the spring. It is therefore important that all the affected leaves should be destroyed in the autumn, and the bushes should be sprayed with a copper mixture in the spring to prevent the infection of the leaves by spores brought from a distance. Many other fungi attack the rose, but perhaps the only other one that merits mention here is Actino nema Rosae. This attacks the leaves, forming large dark blotches upon them and frequently causing them to fall prematurely.
A very large number of insect pests are found upon the rose, but the best known and most formidable on account of their great powers of reproduction are the aphides. More than one species is found upon the rose, though Aphis rosae is the com monest. Their attack should be checked by the use of a quassia or nicotine spray. The larvae of some of the Tortrix moths fold the leaves almost as soon as they are developed from the bud, and do considerable damage in this way and by devouring the leaves, while several "looper" caterpillars are also found feeding on the foliage. Many species of saw-fly larvae are also known to attack the rose, feeding either upon the leaves or devouring the young shoot. These larvae should be carefully searched for and destroyed whenever found.
See Dean Hole, Book about Roses (1894) ; Rev. A. Foster Mellias, Book of the Rose (1905) ; J. Weathers, Beautiful Roses for Garden and Greenhouse (1903) ; J. H. Pemberton, Roses, their History, Development and Cultivation (1908) ; L. H. Bailey, The Standard Cyclopedia of Horticulture (1914-27) ; J. H. Nicolas, Rose Manual (1930), and the publications of the National Rose Society.