Following the first confirmed detection of Septoria leaf-spot disease in Switzerland, Agroscope has published an information sheet to explain the symptoms on lavandin (hybrid lavender) and true lavender and to highlight control options.
In September 2024, an essential-oil producer in the Jura contacted Agroscope‘s ‘Medicinal and Aromatic Plants‘ Group about leaf spots on an organic lavandin crop. Based on photos and samples of diseased plants received as well as a description of the damage, the diagnosis was steered towards Septoria leaf-spot disease of lavender. Microscopic examination of the fungal spores confirmed this diagnosis, since both their size and morphology exactly matched those of the pathogen Septoria lavandula.
