What is Rose Black Spot?
Black spot is a fungal disease that appears as black spot on the leaves of roses. Spores
are easily spread by water splash and infections take hold when the water remains on the leaf for about 6-7 hours.
Areas with high summer rainfall and high humidity usually have the highest incidence of black spot. Treatment of the
disease is year round as the fungus overwinters on stems and leaf litter. All diseased leaves should be raked up and
disposed of. Diseased stems need to be pruned back to healthy wood. Spray roses with a Lime Sulphur spray in winter
and start an early preventative spray program at the beginning of spring once foliage emerges.
What are the symptoms?
Circular or angular black spots on the leaves which are fringed with yellow margins. The spots are black and can also
appear on the stems. The leaves will fall prematurely and if left unchecked can lead to defoliation of the plant.