I have a well kept, healthy, 5ft high, 40yd long, 20yr old Portuguese Laurel hedge. Last autumn the leaves on one plant turned grey/silver, through the winter some branches died. That plant is now growing new silver/grey leaves. The leaves are olive greenish – like eleagnus ebbengei. But, the leaves on three more plants dotted through the row are now doing the same. 25 years ago I lost a viburnum tinus hedge to honey fungus, it was 65 yds away from the laurel hedge, the house is between the two sites. I have lost nothing since to honey fungus. If it IS silver leaf disease, what can I do a)to the olivegreenleaved plants to “cure” them and b)the green leaved plants to protect them? We look at this hedge every day through the kitchen window so its important to us!
All that can be done is to cut out affected branches, when you are convinced it is silver leaf, and perhaps even remove the affected plants altogether as they can be a source of infection.
Plant new plants in their place … silver leaf is not soil-borne ….and allow the neighbouring plants to grow into the space.