Black Spot on Roses - Causes and Cures

'Black spot' is a fungal disease that causes purple or black spots on the foliage of roses, (picture right) the foliage then to turn yellow and drops off. So thats the severe case, in milder cases only some foliage will be affected, and this will depend on the climate, and the type of rose, some roses are more resistant to black spot than others.

What causes Black Spot ?
Its a fungus (Diplocarpon rosae) that thieves it wet humid conditions but can also affect roses in cooler areas.

How do we prevent Black spot?
Good air circulation, never water the foliage, remove all diseased foliage and wood and burn it. When pruning remove all diseased wood in winter.

How do we cure Black Spot
Lots of fungicides are available, in spray form. All do a similar job, however we suggest using a different spray each year and the fungus is very adaptable and will become resistant to an extent.

What about Black Spot resistant roses ?
Yes they do exist and to a certain extent are a great alternative, especially in warmer climates, however the fungus, as mentioned does tend to adapt, so be aware?Ķ

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