Well, it might have been ideal 50 or 60 years ago, but its not ideal now. There are other anti fungal treatments for spraying roses with during the growing season, one being Roseclear Ultra, which should be used fortnightly to manage/treat fungal infection. All leaves should be collected and not left to sit on the ground over winter, to reduce the number of spores possibly being harboured within them.

You can, if you really must, spray your roses now with a solution of 25ml Jeyes in 5 litres of water, or from a can, 110 ml in 5 litres of water, but when used as a drench on soil, its assumed there are no plants present, and replanting is not recommended for a full six weeks post treatment.

Also its often better another time to prune only lightly in autumn and do the harder prune in late winter or early spring, when any frost damages shoots can be removed easily.