Keeping roses healthy
Roses are susceptible to several pests and diseases, and you should be alert to problems as soon as plants start to bud again in spring.
Black spot is a fungal disease that causes foliage blotches that start yellow and turn purple and black. In worst attacks the leaves fall and the plant is weakened.
Protect plants by collecting and destroying affected leaves in autumn and prune out stem lesions.
There are also several fungicides available, plus some ‘double-dose’ ones that contain pesticides.
Pests include a variety of sawflies that affect the leaves and stems, and aphids.
Tackle pest infestations before they get so large that you need to resort to chemicals.