Black Spot Disease

Black Spot DiseaseOn my travels, both with and without ISO14001 clients, I have noticed something in the trees and plants that I don’t remember seeing recently: black, deadly looking spots in the middle of leaves.

Growing up with a green fingered grandfather, I recognised that this was the disease Black Spot. I also realised that it was something I knew very little about other than it spreads very quickly and easily and is something that should be monitored carefully. So it only seemed logical to do my research and put it together as an infoblog.

* Diplocarpon rosae is the technical name.
* Attacks are worst during dry spells, but can begin and continue all year round.
* If left untreated, the disease weakens plants and spreads very quickly.
* The disease spreads through soil, a fungus that thrives in un-cultured soil.
* Proper care of both the plant and the soil can cut the risk and spread dramatically.
* Signs that the plant is infected are: small, round black spots on the top side of the leaf, normally measuring between 1-10cm.
* The fungus lives below the surface of the leaf, so surface sprays are usually ineffective. Systematic fungicides are a much more effective option.
* Immediately upon seeing any signs of the disease, cleanly remove the infected leaves (preferably with sharp secateurs or pruners). Do not place them on the compost heap.
* Dispose of the leaves and debris completely, or preferably burn them in a safe environment.
* The healthier your plants are, the less likely it is that they will catch the disease.

Wiki how has a great step by step guide, with pictures;

Kathy Clements
Kathy Clements
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