Dear Jill,

Thank you for your question. The problem appears to be fungal, so please read the following information and remedy for it. I hope it brings your Otto Luykens back to good health.

Jeanne

Fungal Disease Symptoms

Anthracnose fungal disease infects leaves and stems of “Otto Luyken” cherry laurels. Pale brown spots appear next to the leaf veins and the whole shrub may appear to be sun-scorched. Eventually, the branches may develop sunken cankers. These symptoms are usually worse on the lower branches. Humid, cool spring weather promotes this disease. The fungal spores remain alive in leaves, twigs and other debris around the base of the bush to re-infect it each spring.

Fungal Disease Treatment

Infected branches should be pruned off the shrub and placed in the trash. Disinfect the pruners with a bleach solution between cuts to prevent the spread of the disease. Rake leaves and debris away from around the bush and throw them in the trash. Prune off a few of the older branches to open up the shrub canopy for better air circulation. The shrub usually recovers easily. However, when the fungus becomes a recurring problem, the laurel can be sprayed with copper fungicide to prevent the disease. Copper is available as a concentrate, in ready-to-use form, as a wettable powder and in dust form. Spray or coat the leaves and stems thoroughly, being sure to coat the undersides of the leaves. Begin treating the shrub in the spring just as the new leaf buds swell. Treat it an additional two to three times every seven to 10 days.