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Traditionally, the treatment of roses has been by spraying them with pesticides and plant protector. However, this has a number of dangers which can be harmful both to insects (not pests) and humans. This includes killing ladybirds and pollinators, and rendering the rose plant toxic to humans.
Neem oil is a useful alternative to other, more dangerous, options, and an eco-friendly way to keep your roses free from aphids, spider mites, rose scale, and other garden pests.
Always make sure to apply after rainfall or after watering, and never when the roses are too dry. The ideal time to treat roses with neem oil is early in the morning, on cloudy days, and when rainfall is not expected.