Delphinium black blotch

Delphiniums are striking border plants but can be attacked by black blotch, an unsightly disease that can affect all aerial parts of the plant. 

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Delphinium black blotch

Quick facts

Common name Black blotch of Delphinium
Scientific name Pseudomonas syringae pv. delphinii
Plants affected Delphinium species, monkshood (Aconitum napellus)
Main symptoms Dark blotches on leaves, stems and flower parts
Caused by Bacterium
Timing During wet summers

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