A correspondent writes:
For a better bloom cycle, instead of cutting above a 5 leaflet, snip the bloom just blow the peduncle. This should produce more blooms.
[From A Book of Gardening: Ideas, Methods, Designs, by Penelope Hobhouse, p. 216, some highlights from the valuable pruning advice offered by Sibylle Kreutzberger, a former head gardener at Sissinghurst Castle:] The first thing is to recognize whether a shrub or climber flowers on old or new wood; that is, wood made by the previous season's growth or wood made in the current season.... Those shrub and climbers flowering before mid-June can only flower on growth made the previous season. If, therefore, these are cut in winter or spring the flowering will be reduced. The right time to thin or cut back these shrubs is immediately after flowering. This allows plants the maximum time possible for making new wood in preparation for flowering the following season (i.e., true Rambler roses, etc.)... Those shrubs and climbers flowering between midsummer and autumn, the majority of which will be flowering on the current year's wood. Any pruning is best done in winter or early spring to encourage new vigorous growth. Cut back flowered wood to the new shoots and tie in replacement shoots, shortening them by a third. Prune the laterals to two or three buds in early spring. In July vigorous new non-flowering growth can be shortened.
Pruning Gallicas [This advice taken from Graham Stuart Thomas in his The Art of Gardening with Roses, p. 50:] remove old flowered branches immediately after flowering and reduce the resulting new shoots to the general outline of the bush in winter.
Pruning Hybrid Teas [This advice taken from Stephen Scanniello and Tania Bayard in Roses of America, p. 86:] Hybrid teas flower best on new growth, and they must be severely pruned at the beginning of the growing season to promote strong new canes that will produce large flowers on long stems as well as good rebloom. In general, the closer to the ground they are cut, the more vigorous the new growth and the larger the flowers.