Black spot is a common and annoying disease that can leave your roses with unsightly black spots on their leaves, eventually causing them to yellow and drop. This fungus thrives in warm, humid conditions, and is particularly troublesome in subtropical areas.
To keep black spot under control, start by removing any affected leaves or stems, carefully pick up fallen leaves, and dispose of them (not in compost!). Follow up by spraying the remaining healthy foliage with an organic fungicide from your garden centre.
Afterward, add a thick layer of Sugar Cane Mulch around the base of the plant – this helps stop rain from splashing soil-borne spores onto fresh leaves.
