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RHS reactie op inzending
hellebore black death
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Q. Included is a picture of a hellebore I bought last year in the UK (Harveys Garden Plants). Can you tell me which disease is threatening this plant ?
A. Thank you for your enquiry regarding a problem with your Hellebore. The symptoms observed on your pictures are consistent with the disease called hellebore black death.
We strongly suspect that the disease is caused by a virus and we are currently studying this disease in cooperation with colleagues at HRI (Wellsbourne) and Wye college. The symptoms are blackening and distortion of the leaves and stems. This disease has been found on various cultivars and hybrids known to gardeners as Helleborus orientalis now called Helleborus x hybridus, but too little is known about the situation to comment on the susceptibility of other hellebore species. We have recently strongly suspected a case on Helleborus foetidus.
Black streaking and mottling of the tissues along or between the leaf veins are the main symptoms. The black marks may be in a ring spot pattern or the black lines which pass down the petioles into the main stem of the plant. This blackening is due to discolouration of the plant and is associated with serious distortion and stunting of the affected parts. Flowers are also affected. The problem appears to be on the increase in the UK. Affected plants do not recover. We are still working on confirmation that the symptoms are caused by the virus we have isolated and we are also working on the mode of transmission of this virus.
There are no cures and the only thing gardeners can do is to destroy the plants as soon as they see the symptoms.
Yours sincerely
Dr Béatrice Henricot
Plant Pathologist RHS
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